Voltage conversion of Accuphase A-48

correct observation imhififan, Accus have different wiring colors, despite generic schematic is the same. not sure about resistance, using power VARIAC transformer starting with 0V AC and measuring major operational voltages (for example large cap banks) is the most reliable way to make sure no damage if wiring change is wrong. 

All Accuphase amplifiers and preamplifiers I’ve seen use the same transformer type for US/EU/Japan markets, and therefore it is relatively easy to switch them to desired voltage. 

to verify correct voltage can measure voltage on large capacitor terminals, which should be in a range 50V to 55V

I like your "Dim Bulb Tester” idea imhififan!

it will save thousands of $$ if wire - terminal connections are wrong