I went back through a really old (1999!) post on the subject of Epiphone guitar problems and tracked down a suggestion that is now defunct, but over the years it has moved to new locations.

This is the Mudcat thread: Guitar Repair and our late lamented Alice recommended contacting Net Guitar's Stringed Instrument Division. That doesn't go anywhere now, but in Internet Archive I opened her Netguitar link and it forwarded to StringedInsturmentDivision.com. That Internet Archive (obsolete) URL in turn forwards to https://sidmissoula.mystrikingly.com/. And that one seems to work!

To search Mudcat (because the search at the top of the page is broken) go to Google Advanced Search and enter your search terms in one of the top lines and enter http://mudcat.org in the "site or domain." If you don't enter the entire URL it tries to add a www to the address and goes nowhere. To track down dead links, enter that URL into the Internet Archive's Wayback Machine. You can either capture the information you needed from that old site or find out where they moved to.