if amp is all original unmolested, check date code on a pot or speaker...cause 1964 was last year for Fender Electric ( when Leo was still in charge)then CBS took over in 1965 and started changing the electronics and their circuitry to save a buck and change the sound...if its an early early 1965 you might still have " Leos Circuitry"...(took CBS a few months to begin changing things once they acquired the company..if its a later 1965, you can always use the 1964 schematic to bring yours up to Leo' s specs
