The .001" and .002" undersize bearings are made to compensate for slight wear on a crankshaft that's still round and smooth. If you've got one that checks out on the high side of the oil clearance, or slightly over, the smaller bearings can keep the crank from having to be reground. On a 235 main bearing, shoot for an oil clearance of .0015" to .0025", with a maximum of .003". If it's .004" or more, the 1 or 2 under bearing might be needed. They're still listed in the Federal-Mogul catalog, but they might be a bit hard to locate.
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
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