Were the numbers you listed on a TAG on the driver's side of the T5 or were they cast into the case on top? TAG numbers are the ones that can accurately identify the T5 box. The cast numbers on top of the case are not.
A 1985 S10 box...1352-145, should have 14 splines and a short tailshaft, a mechanical speedo setup, and would not fit without modification. It is classified as a Non World Class (NWC)T5.
The T5 was used in GM, Nissans, Fords,AMC's, Jeeps,Isuzu,TVR and even a Griffith. WC and NWC by application. There are at least 6 different gear ratios. Some are World Class, some Non-World Class.
If the bolt pattern matches your bell housing and your shifter is forward, and it fits without modification, you could try the 26 spline Camaro clutch. However, without pulling the top and counting teeth, it will be difficult to determine the ratio. On an 85 T5, you would use your 56 pressure plate and throw-out bearing and match the disc to the diameter of your pressure plate.
Wish I could offer more info but this is a new one!!
Dave
