These instructions are for a 2003 Civic Coupe LX with manual transmission. Below I use the names of the parts given at the hondapartsnow.com web site. I also give the OEM part numbers, so you can google for images to identify what part is being removed, installed and so on. White clips like that shown below hold many of the plastic trim pieces in place. The clips can either be pried out, or the plastic trim piece can be slid off them. If prying, the chances of plastic on the trim piece breaking are good. At times it seems the only option is to pry.
Disconnect the negative battery terminal and let the car sit for a few minutes. This is to de-activate the SRS system and keep an airbag from blowing up while you work.
Remove the front seats. Use a 14 mm socket and a breaker bar on each seat's four hold-down bolts. You will have to disconnect the SRS plug and one other plug mounted beneath each seat. The yellow SRS connectors have a spring-loaded band that goes all the way around them. See photo below (photo from ericthecarguy.com). Push the spring-loaded band until you feel the spring resistance, and simultaneously pull the two ends of the connector until it disconnects.
Remove the driver's side cowl lining assembly OEM part number 83161-S5A-A00ZA. The last four digits of the part number will vary depending on the color of your Civic. This is item #1 and #2 in the diagram below. Two white clips (item #12 in the diagram below) hold it in place. Pull aft (= straight back towards the trunk) to remove this. If the clips stayed in place on the Civic's body, pry out and store in preparation for re-installation.
Go to the anchored end of the driver's side seat belt, remove the cap (item #16 on the drawing below, part number 81422-SDN-005ZA) on the bolt that anchors the seat belt using a small flat head screwdriver; and remove the bolt using a 14 mm socket:
Remove the lining assembly that serves as the sides of the rear seats. See drawing below. If you do not, the chances are fair you will break plastic parts on the garnish assembly. This is part number 83780-S5P-A11ZA and item number 5 in the drawing below:
Go to the trunk lock and pry off the cover (item #5 in the drawing) shown below with a small slot head screwdriver. Then remove the screw (item #12) that is now exposed.
Pry off the garnish assembly OEM part number 84251-S5P-A00ZA in two steps. This garnish assembly is item #6 in the drawing above. First insert a panel tool under the outboard edge. See the orange panel tool in the photo below. Gently pry straight up to partly loosen the garnish. Do not try to remove the garnish fully just yet.
Now pry the inboard edge of the driver's side garnish assembly. Pry in an inboard direction to unfasten the three clips on the inboard edge. I broke two of the three clip retainers, on the driver's side garnish assembly, due to yanking too much. The passenger side garnish assembly comes off more easily. Here are three photos showing the clips and their retainers for the driver's side garnish assembly. These might help you figure out where and how to pry and pull. In the photo below, the orange panel removal tool is pointing to the three, driver's side, inboard clips that should have come off with the driver's garnish assembly if you remove the assembly correctly:
Remove the center console using the guides on the net. I think this one is pretty good: http://www.civicforums.com/forums/117-interior/155280-removing-center-console.html . I have found some variation among 2001-05 Civic Coupes for removing the center console. Gentle prying with a 5-in-1 painter's tool and panel tools (available on eBay), and alertness for screws holding parts in place, are key. I ended up freeing my Civic's center console only so much. Then I lifted the console a few inches to slide the carpet underneath it.
Remove the driver's side footrest, part number 46991-S5A-A01 and item #26 in the drawing below. You need an allen wrench to remove its upper clip (item #27) and a 10 mm deep socket to remove the lower nut (item #29).
Pry up the front edge of the rear seats with a crow bar. Pry out the black clip in the center of the rear seat support holding down the carpet. Start removing the carpet from the rear, then along the sides, and then at the front. Here and there adhesive attaches the carpet to the Civic body. Just pull gently.
Towards the front you will have to cut the carpet in three places. These will be obvious. The cut all the way at the front beneath the heater unit is a little hard to reach but do-able. The OEM Factory Service Manual has a procedure for carpet replacement in Chapter 20. The only part I found helpful was where the Manual instructs you to cut the carpet at these three places, both for removal and new carpet installation. I did not use any adhesive to re-install the new carpet.
I used velcro strips, with super-strong adhesive backing, to help re-fasten the carpet under the center console snugly.
Proceed in the reverse order, except pry out any white clips that stayed on the Civic body, and re-install these clips in the trim pieces. This is so you just have to push on the trim pieces to reinstall them. The three side pieces that run along the outboard edge of the Civic's floor hook together. Study them closely. They are a little persnickety to re-fasten.
Torque the two front seat belt anchor bolts to 24 ft-lbs. Torque the eight, front seat, hold-down bolts to 25 foot-lbs.
Because you disconnected the SRS connectors underneath the front seats, you will have to re-set the SRS system. The steps for re-setting the system appear about two-thirds of the way down at site https://sites.google.com/site/hondalioness/srs .
Check that your trunk release operates correctly. I did not fasten the screw on its housing correctly at first and had to tighten down a bit subsequently.
One Way To Clean a Car Carpet
Take the carpet and a few lawn chairs to your local carwash. Drape the carpet over the lawn chairs. Use the high pressure rinse setting to wash the carpet. A little Simple Green cleaner or Goop can help, but too much will result in carpet wear and fading. Let dry.
Dye Your Carpet a Different Color?
This guy had a lot of success dying his carpet using Duplicolor Vinyl and Fabric Dye (comes in a spray can):