Okay so i picked it up from my buddy for $50 from when he pulled it out off his 92 gs-r. Just needs some work im replacing the rods and pistons and need to get the the rust out of the cylinder walls should i just use fine sand paper? does anyone have suggestions? also what head could i use if i cant find a b17a1 head? what would be best? The block has been sitting outside for like 3 - 4 months with a trash bag over it