I didn't like my K301 because it shook so bad. And I hear the ones that came with balance gears like to throw them out the side of the block.I'm not a big fan of the K301 lol. Every one that I've had apart needed bored atleast .030 over. Once the rings get worn down the Cylinder likes to wear Egg shaped about 1/2 way down the bore.
Looks like a good straight tractor. Should turn out really nice once you get it done.