Hello acb70,

It can be a bit daunting. I wrote up a rather detailed procedure for adjusting the vacuum as well as modulator pressure in my 1981 300SD (722.303 transmission). I included info about the Gen 1 cars up to and including the 1985 models. There should be sufficient in the document to out you on the right path.

The document is a 1.8 Mb PDF so too large for an attachment on this forum. Send me a PM with you e-mail address and I will forward the document to you.