Ok so I blew one tube in my head and I figured I'll replace all four. Now I'm looking at getting electro-harmonix 6l6eh to replace the ones I have. I would have a problem putting them in? I completely new to the whole tube aspect of amps.
EHX tubes are kinda crappy imo but some people like them. You should just be able to pop em in and go. The + has a bias pot but not sure on test points. I'd go the extra mile and get some decent 6L6s from a reputable online shop, have them match 'em up so they all come to you in a nice tight bias range.

just pull the old ones out and put the new ones in
make sure amp is off and disconnected