Man you have to be careful inside those old amps. I resoldered a bad resistor on a friend's fender deluxe. I thought I had discharged all the caps first but I had miss the housing on top of the chassis with all the big caps in it. Holy shit that thing shocked me harder than I have ever been shocked when I went to apply the solder. The gun went one way the solder the other across the room. I've been hit by 110v before but this was much more violent. Very stupid mistake and a new respect learned for capacitors.