Hello everyone. I wonder if any of you knows how to identify a transmission while it's installed. I have a 521 that came with a L20B and a 5-speed transmission from a 720. The transmission is leaking a bit from the speedometer pinion. That could be an easy fix, but I can't figure out what year/model was the transmission taken from, and I believe I need that info to get the right part.
Per Charlie69 suggestion (thanksCharlie), I'm adding some pics (not very good ones) that maybe a Datsun guru can decipher.
Thanks so much for you help!