I thought the T5 swap was pretty easy actually. There wasn't anything that was a real pain. I had the 4 spd out and T5 in, in a couple days. The hard part is finding a tranny. Once you find the tranny, go buy a clutch disc with correct spline count. Compare length of input shaft and bearing retainer to old tranny, drill mount holes to 1/2" and she's ready to mount.
Zenish, the majority if not all S10's T5's will be 14 spline and are "Non World Class". Camaro T5's had both 14 and 26. The 14's generally came with the V6's and 26's with V8's. Some of the V8's (late 80's) were "World Class" and able to handle a bit more torque/HP. And yes, gear ratios vary.
As far as input shaft length, just compare with your old tranny. The only thing I had to do with mine was shave about 1/16" off the front of shaft. It probably would've been fine even if I didn't but, I just matched it to my 4 spd. I didn't have to mess with the bearing retainer or anything else. All was virtually identical to the SM420 4 spd with the exception of the 26 spline vs. 10.
-David
