That is a nice clean chassis. I would like to find what looks like a RCA black plate 12AX7 (far left in 2nd to last picture) to run in my V3 position. Liking the RCA 7025 I'm running now though. If balanced, that might be one to try in your V3(center position of the 5 front tubes). Still learning myself so can't comment on the undersides. Glad you're enjoying it.