Thank you for the information. The other 2 are TC and PG. I want to rebuild one to swap in but not sure about the input shaft difference from what i see and also i need to use the proper rear bearing retainer and yoke. the PG has a open ujoint and different rear bearing support and the TC doesn't have a rear spline at all (wasn't on it when i bought it) but does have the torque tube rear bearing support. I do have a rear bearing support for a 1940 but the torque tube cover joint looks a little different. The GM heritage site was a great link by the way...
