The shims will only be needed if the clearance is too tight with the cap installed without them. Be sure the shim stock overlaps the bearing shells and keeps them pushed tight into the block and cap. If the bearing gets loose it can move in the block and shear off the anti-rotate tab, or fret back and forth and wear itself out. There should be NO movement possible between the bearing shell and the rest of the engine.
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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