[TV MAN]

It could be affecting things. Not sure. I did note that in other amps that they use longer screws to hold the covers on and use the nuts as spacers, then another set of nuts to hold it to the chassis. Most do have covers on the bottom. Might have even seen the use of fiber washers on some. I'm doing a major clean in my attic and found a bunch of old HiFi stuff that I'm going to check and either sell or part out on the auction site. I'll look at how they are put together and take notes.

Rich, there are still plenty of 6V6 tubes on the auction site, some are outrageous (NOS), others,  if your patient or don't mind not having perfectly matched tubes, they can still be had reasonable. New ones - forget it. Well, there are still some available from the UK, and they are good tubes. I'm also experimenting with some other types of tubes in my other amp build.