http://www.retrorat.com/2012/05/lsx-lm7-low-mount-alternator-diy.html?m=1
credit to the source! this is just the LS1 style that came on camaros and firebirds but most people do not know you can drill and tap the iron truck motor and mount it all up, there is great resources here and they show how to do everything with pictures.
Parts needed. Note this will delete your power steering pump and a/c and add more HP. Plus it will remove that nasty looking truck alternator bracket.
Look at this HIDEOUS truck mount for the alternator. Talk about the MILE high club.
Tap your block here. I screwed in the lower bolt to the fbody alternator bracket and used a pencil to mark dead center on where the new hole needs to be threaded.
Then I drilled the hole a little over an inch deep with a 11/32 drill bit.
Now we need to tap it. Use some tapping oil or watch a YouTube video if your not sure how to do this. Make sure you drill it straight and tap it straight otherwise your screwed and you really only have one shot at this.
Tapping the threads is the scary part. Error on using lots of oil and pulling out (lolz) and cleaning it after each turn.
I ended up cutting my 3/4 in spacers using the ones on the original truck bracket. One was exactly 3/4 the other I had to grind down a bit.
Use your 1/4 – 3/8 spacer on the back side of your ribbed pulley. This should be enough to line it up with your crank pulley. Check with flat edge. Make sure to go from the first rib on the pulley and not the front. When lining it up.
Here is the end result.
It looks 1000X better.
I hope this helps you out. Any feedback is appreciated.