You might check on a clutch disc for an 83/84 Firebird...that's the one I'm running in my 235/T5 truck. Also have run an RCF-4201. These are 9-7/8" discs. They both will have the proper spline count and neither had to be modified. These are for an S10 T5...the Camaro uses a different input shaft with a different spline count.
Just be sure to have the rear of your splines opened up so the disc will slide past (towards the transmission) 1/4-3/8" before you install the disc/pressure plate. I've got some information on the modifications to the transmission and how to complete the install the first time in my Webshots album.
Dave
