McIntosh MR78 tuner repair

Cleaned? I assume more than just dusting it out?

How old is the unit? If from the 1960s, have the filter capacitors in the power supply been replaced recently? If not they are overdue.

There is no magic to it, although it is a bit tedious to do. Getting an MR apart is not so bad, but putting them back together is complicated by the fact that you can't touch the glass, at least on the inside. Gloves help, but I hate the things. Off topic but, I just got my MR78 back from Richard Modafferi. I am just thrilled with the result.

There is a thread with photos answering your question at audioaficionado dot org slash mcintosh-audio slash 4294-mcintosh-mr78-cleaning dot html.

I think this is exactly what you need.