You all should read Forrest White's book: Inside Fender. Forrest was Leo Fender's best friend and right hand man at Fender pretty much right from the beginning and he stayed on after Leo left and has some stories about the CBS years right after Fender/CBS switched from the blackface to the silverface amps.
Those amps are very unpredictable. Some are the same as a blackface but with silverface cosmetics and some are filled with cost saving surplus transformers and surplus parts! This, according to Forrest White...who was there and eventually left in disgust because CBS wanted him to sign off on amps that he knew were garbage.
Lew
