i’m doing a 4l80 swap i have everything i need i ran into a problem with the t case i bought the short shaft to go from 27 spline to 32 but my short shaft is already 32 soo i need the main shaft but i need a part number to it or i will just buy a 4wd 2500 t case if i do that which one i need to replaced it with out doing a lot i know i got to run some wires and run a 4wd switch