I recently had the excellent engine from my salt eaten '77 300D transplanted to an '81 in equally excellent condition.

The mechanic that did the transplant didn't know much about diesels aside from those he had to work on in the army. He is a decent mechanic but admitted having no clue about the in and outs of the vaccum network. He maintained that little leaks in the injection system developed over its sitting making it difficult to start. I got it started at his shop and drove it home (15 miles) mostly in first gear because it wasn't shifting properly. . it finally did shift into second and a MB savvy friend thinks that the vaccum leads to the '81 transmisison are not properly connected if at all.
The '81 apparently has a vaccum controlled (or assisted) transmission that the '77 did not. You all mentioned that back before I did the swap as you pointed out that the transmission from ethe '77 would somehow not fit in the '81. Some of the members favored the non vaccum model while others didn't have an opinion. The shop that now has the car is trying to find the vacuum diagram for that car and is not having much luck though I don't know how hard he is trying.
My Haynes 123 book has nothing about it so I thought someone in this forum might have a lead as to where such information is available. I marvel at the collective knowledge this forum has and enjoyed reading the responses from owners all over the world. I woudl appreciate input from anyone with info in this matter.
Thanks
B.H.