I use sealed pots in open guitars, because at some point dust WILL start causing problems. As long as I was in there I replaced the entire harness. The newer Sheraton has better pickups, but both of the Epis really benefited from upgraded pickups (I put Fralins in both).
I have 3 thin lines: an ES-125, a Dot, and a Casino. The current Epi electronic harness is decent stuff. The advice about playing the guitar stock for a while is good. The first time might be a disaster, but you figure out how to do it.
Oh, wiring a thin line is one of those things that gets easier with practice.
