i have a 50 chevy fastback and i need to put in a new rearend. it has a straight 6 and a 3 spd manual trans and it has a pontiac rearend with 2:56 gears and it moves really slow, i know i need lower gears but i would like to put in a whole new rear but am not sure what will fit..the car measures 48 inches from inside wheelwell to inside wheelwell, and the rearend measures 54 inches from backing plate to backing plate..i know i can go like 52 inches, anyone know what car i should be able to pull a rearend that will fit under my car??any help appreciated