I encountered an interesting problem with my amp.  The volume knob was a little stiff, then started spinning freely with no volume adjustment.  I opened it up, and saw that the pot was and probably always has been broken and has only been working by some magical force that could only be explained as voodoo.  Anyway, I am going to be replacing the pot.  before i dig in again, I was wondering if anyone has replaced the pot in one of these amps before and knows what pot is...