vacuum repair - books, diagrams???

[wheelguru]

I saw a message a couple weeks ago about a vendor that had a vacuum repair manual for $20?. Tried the search and did not come up with much. Does anyone know or remember where to get such a thing? Has anyone used it and was it helpful?
I have been gradually losing my vacuum ('78 300d). At first the locks were slow, then the driver door had to be locked to make the heat go and the engine shut off. Then the engine started taking longer to kill. Now my brake booster still works but I think that is all, I just shut off the engine with the kill lever, and have not had hot defrost since I foolishly dialed the temp wheel down during a warm spell a couple weeks ago.
as per usual, thanks all for the help. -Andy

[BoostnBenz]

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