Wannabe, I've done conversion a few times, and it works very well. The rod is bored out until all the babbit is gone, and a few thousandths are removed from the steel part of the rod. Then, a couple of notches are filed or ground into the rod for the anti-rotation tabs on the insert bearings. The result is a rod that accepts insert bearings, in whatever undersize is necessary to fit a reground crankshaft. The same low-pressure dipper-type oiling system is used as the original babbit bearings have, but the bearings are replaceable, instead of having to look for replacement rods.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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