The very early 216's had a "semi-finished" insert main bearing that had to be line bored after it was installed in the block. Later 216/early 235 mains needed final clearance adjustment with shims even though they were supposedly "precision" bearings. The rods on all 216's and low-pressure 235's were Babbit-lined and had to match the crankshaft diameter- - - -when a crank was ground undersize a corresponding-diameter set of reconditioned rods had to be installed. The rebuilders that did a really top-notch job did the Prussian blue/scrape-fit procedure to assure a perfect match between the crankshaft and the rod bearings, then set the oil clearance with shims.
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!