No crankshaft modifications are necessary for an insert-bearing conversion. The same splash-oil system is used to lube the rod bearings. Some people insist on making a silk purse out of a sow's ear by drilling a 216 crank for pressure oiling. It's an absolutely unnecessary waste of time and money.
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!