Guys, don't offer advice about things you don't understand. Adjusting rod and main bearing clearance by changing the shim pack was something we did frequently on the Babbit-rod engines back in the 1950's and 60's. I sent him a PM about how to do it.
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!