This trans came out of an early 1970 Chevelle SS396 L78 that I bought at the Pomona swap meet in the mid 80's.
The person I sold it to converted it from bench 4 speed to bucket auto, changed the colors and it was a feature car in Super Chevy way back then. I bought the trans from him as an extra for my 70 M22 Z28 (knowing way back then that it was a one year trans, JUST IN CASE anything happened to mine).
FFWD to today and his brother inherited the car and wants to change it back to the 4 speed and wants the "original" transmission for the car.
IIRC a thread I was looking at (and can't find today) had VERY similar numbers stamped into it and some suggested it was a replacement trans.
Here are the pictures I have and your input is appreciated on if that theory is fact or ???
Thank you for your opinions / facts / insights, etc
