I need some input on a 1000hp 727 trans

fishy68 said
The 76 trans they changed the spline angle on the output shaft in 76 (and again in 91) so you need a 76 to 90 4 pinion planetary to upgrade.

Is this 76 a good thing or a bad thing , I can get a 73 or 74 core maybe I know a guy who has a few I would have to go trru the pile to see if there is on there.

One another note I pulled the pump out of my 1970 727 that was in the car and I think that someone swapped the pump support out for the wider 71 and up if I'm rite please correct me if I'm wrong .

Here's some pix

Thanks Mike