Machining the rods is pretty simple if a shop has a Bridgeport mill and a micrometer-adjustable flycytter/boring head. Bore the Babbit metal out, and a little of the connecting rod to a diameter of 2.403"-2.404". The boring operation should be left about .002" undersize and the finish diameter needs to be done with a rod reconditioning hone. The part number for the rod bearings is TRW # CB-503B or Federal-Mogul # 1415SB.

Currently, rod bearings are available in .010" and .030" undersizes. .020" under bearings are almost impossible to find, ditto for standard diameter rod bearings.

It's also possible to fit rod bearing inserts for certain applications of Perkins Diesel engines and Komatsu Diesels with a little more tinkering and fitting. Those bearings are available in a wider variety of undersizes but they're not a drop-in fit like the dedicated 216/235 rod inserts.
Jerry

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