I used an Astro van disc in my T5 swap. I have a 10 in. flywheel and pressure plate and the Astro disc is 9 1/2 in. It works perfectly. If the disc is slightly smaller than the press. plate and flywheel, it will grab better. The guy at the clutch house said they actually installed a 10 in. disc with a 11 in. set up, in the early Camaros for that reason.

Good Luck

'54 3100-235-T5 trans-12 bolt 3:31
'68 Impala 307/350
'78 Sportster/Original owner