I remember getting called in to evaluate an oil-burning problem on a Ford 302 engine rebuild by a local shop when I was running the state trade school shop in Pulaski, Tennessee. After doing several diagnostic procedures without finding any problems we finally tore the engine down. One piston had been installed with the oil ring missing! I think the guy who did the rebuild had a chronic problem with Budweiser fever while he was on the job!

When you pull the pistons, be sure and check the cylinders for taper wear. If there's more than .005" of taper, it's very unlikely the rings will seat well, or last very long. At 2,000 RPM, the rings in a taper-worn cylinder are changing diameter 66 times a second trying to maintain contact with the cylinder walls.
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!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!