Hey all, I recently picked up a 1969 Fender Bassman with an ac568 circuit with the intent of having the biassing modded to the aa864 circuit spec. When it arrived and I peaked at the circuit (I know very little) it looks like the telltale tan resisters of the ac568 circuit are already gone. I had read in a different post those resisters can’t be removed without altering the biassing in some fashion, either to the ab165 or aa864 spec? Any chance a circuit guru would be able to tell a nontechnical fool like me what may have been done based on the pics below? Much appreciated!