T looking thing is called snap gage. Thats a rough idea. A dial bore is some thing you move up and down the cylinder thats the best way I can describe it Machinist use when boring or hone a block. Most stock pistons ( just as example) lets say they require .005 thousandths piston to wall clearance.
So the question is what did you come up with for piston to wall clearance. Then you have to take into account what its going to need to clear up and get ride of that ridge. Which more then likely cause the broken rings. And yes if you call machine shop and say I want to bring in my block and have you check the bores for me, and see if I can just re-ring it, with the emphasis that you don’t wanna leave the block you just want to check it. Done it what quite a few times.
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