Do a good cleanup on the tops of the pistons, and see if there's an oversize stamped on top. That will be a deciding factor on whether to consider another overhaul. If it's .060" oversize or more, chances are another block will be a better choice over rebuilding that one again. Standard bore, or oversize cylinders in the .030-.040 range will have some more block material to deal with. Next, see about how much "ring ridge" there is at the top of the cylinders. If you can hang a fingernail on a pretty noticeable ridge at the top 1/4" of the cylinder where the rings haven't been running, it's probably time for a rebore and new pistons. New rings don't seat well or live very long in taper-worn cylinders. Most of the wear happens in the top 1 1/2" of the cylinder, which means the rings are constantly flexing to try to maintain a seal. At 2,000 RPM, those rings are changing diameter 66 times a second! a straight-bored cylinder eliminates the ring flex.
Shimming a Babbit rod isn't rocket science, just remove a shim to tighten up the oil clearance a little, and either check the fit with plastigauge, or use the old standby method- - -put a narrow piece (1/8") of .0015" shim stock between the rod cap and the crankshaft and remove shims until there's a very firm drag- - - -(not a lock-up) as the crank is turned a little. Then be sure to remove the checking shim, and move on to the next rod. The bearing material is bonded to the rod- - -no bearings to replace. Reground crankshafts require changing rods to match the smaller journal size.
A stovebolt engine comes out of the frame easiest with the transmission unbolted, and the bellhousing still attached to the block. Support the transmission with a jack as the engine is lifted and moved forward off the mounts. Pull the radiator for sufficient clearance to slide the engine forward as it's lifted off the mounts. good luck!
Jerry
