I think before pulling the board I'd want to check the functioning of the output section and the power supply. Check the main power rails are ok. I put a new PT in one of these two weeks ago. As far as I recall the rails are something like +-70vDC, but i can't check now and I never had a schematic. But checking the rails are equal voltages would be a start. And that there is no DC on the output. Power amp problems usually result in silence and blown fuses but you never know.
If the power amp checks out you have a smaller section of the circuit to look into - the part between the return and the power amp.