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Alright, next on the list of pedantry - tightening of the connecting rod cap screw/nuts. The bearings all look about like the one below, which seems to match what the manual describes for normal wear, so I'm going to leave them alone. The service manual says these of the 7/16 variety should be tightened to 60-65 ft. lbs. Questions on this,

- I assume these torque specs were for a dry (no lube or Loctite) installation. Can these nuts be reused, or should new 7/16-28 self-locking nuts be used? I will say, a quick perusal of McMaster doesn't show a lock nut for 7/16-28. Their two options are a regular 18-8 stainless steel nut and aluminum for that size.

- Either way, is it a good practice to use Loctite (red or orange) when installing these?

Anything else I should be thinking about when reinstalling besides ensuring the oil holes point toward the camshaft side of the engine? I've got the top and bottom rings facing the opposite side of the slot on the piston, and the middle ring facing the slot.

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You don't need Loctite on any of that. You can buy new nuts from McMaster but IDK if it's necessary. The torque, rinse off the heavy oil with gasoline or the like, and hit it with something like PB Blaster just to get it wet.

Remove each bearing shell from the cap one at a time, and clean the mating surface on both with brake cleaner so it's dry between the bearing and cap. This reduces the chance of a spun bearing. Obviously you must use oil or prelubricant paste on the bearing surface itself.

Those are Marsden nuts and used in countless applications throughout Packard (they were invented by a Packard engineer), then later by other manufacturers. They should be readily available online.

If I was that far in, and with new rings, I'd replace the rod and main bearing inserts. That would assure long wear, good oil pressure, and good oil control.

Here are the new nuts:mcmaster.com/94820A245/

As long as you can't thread the old ones on by hand, you can probably reuse them just fine. If they spin on no problem then it's best to replace.