I need to know where to get a manual for rebuilding a 700 tranny out of my 88 IROC. It will be my first transmission, so it needs to be a detailed one. I would also like some advice on how to strengthen the trans and get some firmer shifts.

Why not give Pro Built a call. I am sure he has or can get the ATSG manual and he sells all of the parts too.

I just got mine rebuilt by a trans shop,but I had them put TCI extra clutches in the 3rd,4th gear sets. I put in a Fairbanks piston servo kit also. The car will jerk a knot in your a$$ now when it shifts to 2nd and 3rd.
Give Fairbanks a call and get a piston servo kit,they rock.

I would only use the TransGo Reprogramming Kit in your tranny. While if you use the Reprogramming Kit it will give you firm shifts at WOT it is not about making harsh shifts which shortens the life of the tranny. It is about fixing the causes of complaints and failures in your tranny, some of which you would not really know anything was changed, it just works correctly now. I know allot of guys who use the broken Sun Shells out of 700's as stands to set pumps into on assembly since there is no shortage of them. That bang 1-2 shift feels great until you lose 2nd and 4th and reverse to boot.

It's 3:13 in the morning and I needed a laugh, thanks leo!.