samuel,

no, thank you. no need to apologize. your thread got me at least thinking about the ins and outs of the vac system and its relationship to ... well, just about everything. i thought that at least there were some universal rules that applied to both 617 and 603s, but i was wrong.

i obviously have a lot to learn, but thanks again for being so helpful to everyone.

Bob,
Early this a.m. [ the clearest time for my 65-year-old mind these days ] I did a little of one thing I think I'm really good at regards to this, our BAD MBZ habit... I did some browsing in an effort to see IF I could contribute to your project. I have also read some of your "blog" and find it to be really well written... cudos! So I will be joining your blog... at least to the extent that I see I can be useful... and my 1st contribution there will be something I found in Russia that might be useful... parts blowup diagrams and their accompanying tables of P/N(s) I thought you might find of interest IF not outright useful !
Regards,