Thanks for the follow up. I understand regarding the port size. Since I have a 124 (1987) 300D, it actually has two separate lines coming from the Vacuum pump. The brake booster line seems to be fine and I have nearly 25hg of vacuum on this line. The clogged port is the other one. I have no problem with replacing every vacuum hose on the car. I think, however that I will start by replacing the white plastic junction (for lack of a better term).
One more thing, if I may... I want to disable the EGR valve as I am fairly certain that this is the primary source for the crud in my vacuum lines (The overboost protection line was full as well). When I check the EGR (hot), it does not hold vacuum. Will simply eliminating the vacuum source defeat the EGR valve or will I need to fabricate a block off plate?
Again, many thanks!