It has a replacement OT, has a white sticker that says 'JMP 100' and '2000' underneath, assuming thats the year it went in. The circuit looks pretty stock, mustards and some orange drops(?) In their as well. I'm not a tech but I compared the pics I took to others I've seen on the web. Tried to upload them yesterday and they wouldnt. I threw some tungsram pres and Siemens/winged Cs in there..all 4 bias up right around 36. That's as high as I can get them though. Its very fat and warm sounding. I like this better than any other JMP/JCM master vol I've had. OT brings the value down but it sounds great...right now I'm not sure which sounds better, Jubilee or JMP!