Well, CR, I think that we have, in this discussion, focused on the shops' indifferences and lack of tool inventory rather than trying to find an interested and knowledgeable mechanic for our particular purposes.
As a case in point, I have recently done a complete Eisentraut renovation which, in addition to its new Ed Litton paint as it was pretty rusted, was an eclectic parts assemblage similar to what many Eisentrauts received back in the day (1977-8), to whit: Shimano Crane rear, Simplex wide range front, Stronglight 93 cut-out with drillium, OMAS Ti BB, Chris King very early Santa Barbara HS, etc. This kind of a setup required a very special and understanding mechanic as I thought I knew basically what was involved in changing over from the newish Shimano stuff that the frame had when I received it but that did not turn out to be the case.
It seems that many parts had their own particular nuances and my mechanic , who goes back to being a riding partner of John Howard in his youth, and someone I met through our mutual mountainbiking going back to Crested Butte, had to be consulted. He explained to me the stack height dilemma my headset posed because of the last Shimano headset stack height's incompatibility with it. No problem, he called Chris King and turned out they would have a part in the back somewhere that would solve the dilemma. Bottom line, we got to use the NOS Santa-Barbara-days headset with all but one piece substitution. You can't tell by looking.
On the OMAS unit, he immediately said that, back in the day, there were issues with them (not just Italian threads BTW which Eisentraut used regularly-- yes he had the tap!) coming loose. Locktite would sometimes be necessary back in the day (I do remember this exact sequence on my OMAS in a Vitus in 1981), but, he explained, Locktite's formulations have changed over the years and the color to use now in order to have the setting hold and still be able to service the unit if and when it may become necessary, is not the same as then. After roadtesting the basic installation, he deemed Locktite would be needed for security. Again, interest, experience and knowledge is necessary, not just a shop's or any person's inventory of tools let alone biases against old stuff.
And that knowledge is something we all keep acquiring, especially from the collective wisdom right here.
Ken Wehrenberg, Hermann, MO