Whilst shimming my devol rad guards today to get rid of an annoying rattle, i noticed a crack in my tank around the top radiator cover bolt. Whats good stuff for repairing this? It doesnt leak, so mustnt be cracked all the way through, although you can see a line from the inside. Sounds like a good excuse for a YZ tank/seat. I'm guesing I'll have to change the rad covers too?