One bit of advice concerning machinists. If your guy says you can run standard bearings on a reground crank, you need to RUN- - - - - do not walk- - - - - away from him, and take your engine with you! He's going to cause you untold expense and grief before the job is finished. I was GIVEN a 261 engine that was assembled with standard bearings on a .010" undersized crankshaft. It ran less than 20 minutes after a complete rebuild and ruined the crankshaft.
The tab you highlighted is the one to look for. The design was changed in the mid-1950's to make it easier to change main bearings with the engine in the vehicle. The ones with the big dowel pin in the upper bearing requires the crankshaft to be lowered nearly an inch before the upper shell can be replaced. The one with the tab at the parting line can be rolled out by lowering the crankshaft just a few thousandths. Shims between the block and the cap supposedly were eliminated when the design changed to use the tabbed bearing, but I've seen them used on the later model bearing on rare occasions. If the crank locks up or gets very difficult to turn when the caps are tightened, I suppose using shims will be OK- - - -the idea is to get as close to .0015" oil clearance as possible, either by grinding the crank to fit the bearings, or shimming. Good luck!
Jerry
