That snapgauge cannot find the fine measurements that
can spoil your project likidy-split. You have to measure it with a dial-bore gauge.
Your bores could be curved in side view or even S-shaped and the snap gauge won't see it.
Your bores could be tapered from top to bottom, and snap gauge can miss that.
The top inch or two are the most important, and the very top .500 even more so. Even just .001 variance in that last inch is important because the ring-gap varies by over triple that, (3.1416) for that .001 inch of wear.
This makes the rings move in and out of the grooves and accelerates the wear on the bottom of the land. Additionally the piston might want to rock over to the thrust side, exposing more ring on the opposite side.
If you gap the rings in that .001 larger area to the correct factor, and they close up as the piston moves down that might not be a bad thing ..... unless they cloose to zero, then chit happens. If you compensate for that by adding gap, then you loose ring-seal.
I'm not saying your particular engine has this problem. What I am saying is that the telescopic gauge is not the right tool to prove it with. IMO, you should hire somebody to measure all your bores with the dial-bore gauge. The tool is too-expensive to buy for a one-time use, and you really need someone with experience, to set it up and read it....... correctly