Thanks for the replies checkmate and blue thunder.

I believe the actual damage occurred last year at a Poker Run. I have the boat propped a little light (to help it get on plane better with my normal kids, wife, coolers so on and so on), so when running in Poker Run mode (light load, trimmed out, running full throttle for a couple of hours, etc) I bump the rev limiter (5400 rpm). I picked up a bad miss at a poker run last July but it cleared up when I changed plugs, in reality I think I damaged the piston then and that is what fouled the plug. The mechanic said there was a lot of carbon in that cylinder so it had been hurt for a while.

The reason I lost compression is that I blew the head gasket the last weekend I ran it. I picked a miss that weekend also.

I will change the wires though as a precaution.