Genrad 1659 RLC tester

Anyone familiar with these testers from the USA, about 1991.
I have the service manual with schema but just in case anyone has dealt with
repairing them, may have a few leads.
The company that uses them for post-production test has only one more spare,
so they would like these 3 repairing. The faults always seem to be failing
to complete the POST self checks/initialisation. Often due , apparently, to
sometimes static electric type voltages on production of the capacitors when
they come off the line in certain situations, not normal , but can happen in
rare combination of events.