who knows about GM clutches?
 

OK this isn't about V8s, but I figured you guys would be the most likely to know.

I am trying to figure out what clutch disc is right for my ZF S6-40 (90s corvette tranny). When I look it up, it comes up as 1.125" x 26 splines, but all the 7.25" clutches only list either 1.156x26 or just say GM 26 spline.

Are all GM 26 spline input shafts the same and this is just a rounding thing or are there actually two sizes and I need to figure out which one I need?

For the curious among you, this is going in a FD behind a 3 rotor, which is why I need to use a tilton style clutch with my custom bellhousing.

It should be the standard GM 26 Spline that the T-56 and TR6060 use. Not to sure how the length works out in your application but that is a bad little transmission.