> So, how should I clean this thing ? My thought is to simply open it up
I think that you have the correct idea, wash it down well, let it dry a few weeks, then give it a try.
As long as it wasn't turned on while wet(or was busted before being tossed out) it should work.
Most electronics can get cleaned this way(except things that the water can't run out of properly like hard drives, etc).