Those are MINIMUM end gaps. It's possible to get by with somewhat more gap, but it's important that the ring ends don't butt together as they expand from temperature. If you're planning on doing a shade tree job with badly-tapered cylinders, the ring job will be very short-lived. Unless the cylinder wall taper from top to bottom of the piston travel is less than .005", the rings will flex constantly trying to maintain contact with the cylinder walls. At 2,000 RPM, the rings will be changing diameter 66 times PER SECOND! Good luck with that!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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