Thanks for your help G1 I appreciate it. I will leave the transistors alone. It looks like the trace from the pad marked "4" goes into a resistor (R28) and then into the tip and ring of the phone jack. So I believe 4 is positive speaker wire and 5 must be negative. This is a restoration project for my brother in law who is a gifted guitar player. I am trying to cheer him up as he is going through a bad break up.