If you choose to use the 26 spline shaft you'll need to check out the info listed in the "Hybrid T5" Tip to relocate the speedo "drive gear" on the mainshaft. In reality I can see no use for changing out a 14 spline shaft for a 26 spline GM transmission when you can get the whole T5 "Z" V8 transmission for a couple hundred bucks. The only real problem you're going to have is with the Camaro disc/pressure plate on your flywheel if you're running it behind a 216 or a 235. Several have made the change to the "Z" box which has much better ratios all the way up to the .63 5th gear.
As for the clutch plates behind the .72 0r .86 T5's I've used the RCF4201 from NAPA and also the disc from behind a 2.8L 83-84 Firebird in my 235 truck. They are a 9-7/8" disc and I outlined the process to make the transition work the first time....in my Webshots album. Hope this helps you both.
Dave
