Thanks for the replies so far. I'll do all the things you mentioned in regards to waterproofing and the wing gasket. These are the kinds of things I'm looking for.

The gas porting thing is where you drill 4 small holes in the top of the piston that go directly into the ring land. I think the factory YS pistons have 4 notches cut into the top that go into the ring land.
Either way, the idea is for compression to get behind the ring and really make it seat. I used a needle drill that I drilled by hand.
I guess the diameter of the drill is about .040 +/-