My '72 360 has already been bored .030, and there's a bit of a ridge in the cylinders. It was rebuilt stock many years ago. Would it be safe to bore it another .010? Bummer is, I already bought a set of .030 over KB191's for it, and I'm concerned putting them in with the ridge there.
I don't know your situation, I assume the block is thoroughly cleaned, so you can say for sure it is a worn ridge. But I've seen some mopar blocks with what 'appears' to be a hefty ridge is sometimes mostly carbon and gunk.
I don't think they can bore just 0.010", but a good machine shop can machine hone 0.010", of course it has to have sonic Okey dokey, like has been mentioned.
