How many hours are people waiting to do the top end on the 350's? I have 82 hrs on mine and am debating on whether or not to slap a new piston/rings in her within the next few months. I've read some things about pros running 50 hrs on rebuilds (enduro guys) and their motor still in like new shape. Also, how much have you had to spend on a complete piston/rings/gaskets. It looks like the piston is around 200$ and another 55 for the head gasket and 5 for the lower gasket.