Installing a '03-'04 Porsche

glass top and frame

on a '97-'02 car




Copyright 8 2009 Maurice P. Fedida


I'm fairly clueless when it comes to electric matters in a car, so I have to give credit to Boxsterra and Disraeli of, and to Atta of for their invaluable help in sorting out the electrics and making it work like 'factory'.  Boxtaboy also gets credit for his infectious optimism, resourcefulness and useful hints and tips.  I have tried to make this DIY as thorough as possible so that even someone with limited DIY skills will be able to follow all of the steps and accomplish this modification. 

              The estimates for the prices of parts listed are as of this writing (Sept, '09).  

             Of course, as an attorney, I don't guarantee the results, and if you decide to use this guide, you do so at your own risk!

The advantages of installing an '03 or '04 OEM glass-windowed top onto an earlier Boxster are many and substantive, the disadvantages are few and subjective.


The perceived advantages include:


1.  With a glass-windowed top, you never even need to look back in your rear view mirror to see how the top is folding anymore. To quote Boxtaboy: 'It's grrrrreat!!'.

2.  You can put the top down in any temperature without concern for cracking the vinyl window, so it can greatly extend your top-down season.  There's something special about driving with the top down and the heater on.  How many times have you wished you could put your top down when temperatures were in the low 60's but you had that nagging feeling that your window might crack?  No more such worries with a glass window.

3.  No need to get out to do the 'chop' to make sure the window is folding without creases.

4.  The clarity of the glass does not degrade over time.

5.  It's much more updated and clean looking.  The plastic reminds some of us of a shower curtain, and makes the car look dated.  Convertibles these days, from Ford Mustangs to Chrysler Sebrings to Mazda Miatas come standard with glass.

6.  It has an interior liner that makes the interior feel more like you have a hardtop on the car with more sound and heat insulation.

7.  It has a factory heated rear window for defrosting which plugs right into the defroster connector which is pre-wired on all Boxsters.

8.  It's also less likely to be slashed by vandals.

9.  True, the '03/04 window is a bit smaller than the plastic window, but larger than the GAHH or Robbins window.  The aftermarket units must necessarily be smaller so as to allow the top to fold without the benefit of the 4th bow.  That design puts a great deal of stress on the glass window, which is why the initial batches of the GAHH and Robbins glass-windowed tops had problems with their windows separating from the canvas.  The OEM glass-window also does not restrict access to the engine compartment as much as the glass-windowed aftermarket tops because the OEM top has a 4th rib in the frame which allows the window to completely tilt up and out of the way when you put the top in the service position.  Also, as an added bonus in the OEM version, you get the letters 'PORSCHE' etched into the lower center portion of the glass window and you get a built-in strap sewn into the underside of the rear main bow for holding the rear of the top frame up and out of the way for easier access to the engine.

10.  And finally, you never need to polish or worry about the plastic cracking, and unlike some of the aftermarket glass tops, there is no concern that it will separate at the stitch seams. 


The perceived disadvantages include the following:


1.  Some don't like the side profile of the 4-bow frame that supports he 03/04 OEM tops, and prefer the profile of the original 3-bow top with the vinyl window.

2.  The OEM glass-windowed top is slightly heavier because of the glass window and the addition of the roof liner, which did not exist on the earlier 986's.

3.  The OEM glass window is slightly smaller than the vinyl window.

4.  The car is not 'correct' according to purists.

Here are the before and after photos along with some photos of the GAHH top installed by ddb of, so that you can judge for yourself whether this mod is for you (you can left click on the photo to get a bigger version of the picture in most browsers):


For me, it's something I have wanted to do since I first realized that it was a 'simple' bolt-on installation.  The length of this DIY guide belies the simplicity of the project, which will be evident once you have completed it.

While a brand new OEM top and frame assembly would be prohibitively expensive for many considering this option, reasonable examples in good condition can be obtained from those parting out their '03/'04 Boxsters when they are setting up a dedicated track car or from dismantlers.  I have seen prices ranging from about $750 to about $2,500 at various dismantlers for a used glass top in good condition.  You can go to '', and select '03 Boxster or '04 Boxster, and where it asks you what part you are looking for, type in the word "ROOF", and then in the next screen, check off "soft top, roof". It will then show you all the available '03 or '04 tops (either with the frame or not), and each dismantler's asking price.  There is also a descriptor for the condition of the top, as evaluated by the dismantler.

Unlike an aftermarket teardown and replacement of the canvas part of the top, which, on a scale of 1 to 10, with 10 being the most difficult, I would rate at about an 8, the replacement of the complete top and frame assembly is only about a 3 or 4.  If you add on the electrical part, which is only required if you are doing the installation onto a '97 to '99 Boxster, that will only raise the difficulty level to about a 5 or 6, depending on your electrical and soldering skills.  If you have never done any of these before, count on about 8 to 10 hours for the first task (covered in another section of Mike Focke's website), compared to about 2 to 3 hours for the removal and replacement of the complete top and frame assembly, and add on about 2 to 3 hours for the wiring, if necessary.

There are three distinct parts to converting the earlier vinyl windowed tops to the OEM glass windowed tops: the mechanical aspect of the replacement of the complete top and frame assembly and two parts of the mechanical installation of the new transmissions and the electrical rewiring and modification, when needed or desired.

You will only need to deal with the electrical part of this conversion if you are fitting an OEM glass windowed top and frame assembly onto either a '97, '98, or '99 Boxster and then only if you decide to install the later-style 'B Version' transmissions, parts and relay.  The electrical wiring in the latter case will involve work near the driver's side transmission, near the driver's side of the electric motor, and behind the relay tray.



'97 to '99 'A Version' Transmission


'00 to ‘04 'B Version' transmission


You can install an '03 or '04 glass windowed top on any of the earlier 986 Boxsters (1997-2002), which all came with a vinyl rear window from the factory.  If you plan on installing one on a 1997 to 1999 Boxster, and want the more reliable operating system, then you will also have to replace the 'A Version' transmissions, mounting studs, cables, and double relay, as well as doing some rewiring in the areas briefly described above.


       Note that if you don't want to do any rewiring on your early Boxster ('97 to '99), you can still install the OEM glass-windowed top and keep the old 'A Version' system which includes the less reliable 'half-moon gear' transmissions, the non-crosshatched cables (i.e., prone to stretching), the 'B-Pillar microswitch', the 'lever' microswitch on top of the electric motor and the old 'A Version' relay.  In that case however, you will have to devise a way to trip the B-Pillar microswitch at the appropriate time in the cycle because of the new location of the B pillar on the new, 4-bow, frame.  As a final variation, the newer 'B Version' transmissions can also be made to work with the early electric components (i.e., B-Pillar and lever microswitches and old double relay).  The electric motor remains the same on all versions.


Boxtaboy and I did an OEM 2003 glass top conversion onto his 2001 Boxster a couple of months ago and it went smoothly because there were no wiring or other modifications to make.  There were a few adjustments required after the installation but they were easily solved.  So, for model years 2000 to 2002, bolting in an 03/04 OEM top and frame is pretty much a plug and play operation that requires no re-wiring whatsoever.


At this point, you have a description of the cost, difficulty and the advantages/disadvantages. If you want to do it yourself, you'll need the complete instructions.  Rather than format 40+ pages of text and pictures for you, Mike elected to just u/l the .pdf files and have you download them onto your machine as they are better formatted and you can print the sections you need on a color printer.  If you have a '00-'02 car, you don't need the electrical portion.

Links to the complete directions as .PDF files.

The first file is just a repeat of the comments above on what parts are needed, the costs and complexity.


Mechanical directions for removing and installing the top


Electrical modifications to improve the drive mechanism on a '97-'99 car.