I went to the shop and asked about all of this. He said not to worry about the scratch and honing. It doesn't change the clearance enough to make a diff. He let me borrow a tool that will file both ends of the ring at the same time, so it will stay round. told me what clearance I need, which came out to be about .004 for the bore size, and showed me how to check that. I checked a few other pistons which came out ok. and when the main and rod bearings are torqued to speck, I can barely move the crank with the counterweights. But that is barely with all my weight pulling/pushing on a couple of counterweights. So I think I'm good to go on until the next road block I get to.
