Rebuild in progress - can't turn crank?

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All bearings need to be put in dry during assembly, I always cleaned with lacquer thinner before putting them in. They will get oil behind them to prevent rust on there own , have never seen rust behind a bearing on a rebuilt good running engine so I wouldn't worry about that. Ive seen engines assembled that guys couldn't move the crank where oil was put on the block and back of bearing during assembly. We ALWAYS measured the bearings in the block like PGSIGNS outlined above, then ground the crank to fit .I was a crankshaft grinder for 20plus years. .0003 or three tenths on the low end is guaranteed to fail as they're showing in that manual , even .001 will fail eventually. I would be at the high end minimum for main clearance but as I've said I still "like" .002-.0025 IMHO . GM on an assembly line to gain clearance or reduce clearance had a wide range of over and under bearings even for a standard ground crankshaft. I can pretty much guarantee GM never assembled an engine with .0003 to .001 clearances