[Brad]

Originally Posted by jimfulco

Might see if a local parts place would let you buy both, then give you a refund for the one that won't fit.

If it's the smaller, you might want to look into a 10.4" clutch. My old 6-cylinder Nova ('69) came with a 9.125" clutch, but a 10" disc for a 307 fit, using the original pressure plate. I was pleased to find out that a 10.4" pressure plate and disc for a 350 also fit on the same flywheel, and was an even greater improvement than the 10" was. The 10.4" did require a shorter throwout bearing, since it had the bent-fingered diaphragm, whereas the others had a flat one. I don't know how much of this interchangeability applies to trucks, but it wouldn't surprise me if they're similar.

Yep, they're the same. I just went through this with my T-5 swaps. Was gonna go with 9.125 but found a 10.4 that fit in the pressure plate. I ended up taking it back, but for an unrelated reason.