Just to update-

De-Oxit seems to have made it better, but not 100%... sometimes it still cuts out. Repeat doses might solve that.

In the meantime, I've talked to HQ about a quote for some drop-in replacement pickups and Vol./Pan/Filt./Q-3 controls for them. Of course adding the Q-switch means having to drill an extra hole, but I can live with that... it's definitely worth it for the extra available tones. Besides, it's just one little tiny hole.

Did some measuring, and there's plenty of room in the control cavity already. Don't think any routing will be needed, even with adding a 9v battery. (these basses were passive) The catch is the pickups themselves - a mold may have to be made. There's also a possibility if an existing pickup with a wide enough aperture can be used, I might could fit it into the stock covers. Sent those measurements too. So we'll see what comes back...

It's crazy I know... but I had to at least check.   

   

I could have sworn they made a drop-in replacement Thunderbird Activator? OK, I looked, and there is something listed as "Gibson humbucker shape". But I think that's a regular guitar style humbucker now that I think about it... http://alembicguitars.net/prod/pickups.html