Its a 1968 M20.. It was built in sept of 67 for the 68 model year. It has the correct side cover and tail housing. That transmission has a 1" cluster pin..
All-in-all a good transmission to have... If it's clean and the sincros are not bad then i guess you have a winner.... Remember you need to have the transmission and the cover in the second gear position to get the side cover back on...