I have been involved in machining the babbitted rods for insert bearings. We would melt the soft metal out of the rod with a torch, then bore the big end a couple of thousandths under the reccomended diameter in a Bridgeport mill. The final diameter machining was done with a Sunnen rod hone. Yes, the bearing material is very thin, probably less than .030", IIRC. Hand-pouring new Babbit would be a real PITA, unless you machine the groove in the rod deeper first to take a thicker layer of bearing material. The X-shaped groove in the bearing for oiling would have to be hand-cut, also. I'd sugget you bite the bullet and get the rods machined for insert bearings.
Jerry

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