Cool thx for that info. I will look into this . I can’t see the pics , getting bad reception on my phone at work. I’ll give it a look laterCongrats on the find! I have one also. I found the overdrive preamp a bit too harsh for my taste so I converted it from grid-leak bias to cathode bias. It was easy to do and reversible if you want to sell the amp as original. I just copied the schematic for the Gretsch 6151 amp. The amp sounds much better at both low and high volumes.