[Intercooled]

I have never trailered anything, ever. I'm looking into buying a bass boat. I assume i would need an offset ball mount? what offset? I know the trailer for the boat takes a 2" ball. Also The plug adapter for the trailer thats mounted on the bumper of the H2, is there an adapter or something that goes to the trailer wire harness. I noiticed the adpater plug on the bumper looks round and the trailer wire plug looks like a 4 prong straight male plug. Pardon my ignorance, but I have never trailered anything.