Pete--there isn't counterweight on the #3 main so you will need to pry on them up front one way and at the back the other--you can check the endplay with a feeler guage at the #3 main--pry one way, measure, pry the other way, measure to verify(should be same both ways) In this situation you are only looking for causes of the metal and the thrust flanges are one common source of brass/copper type stuff.
Yes some engines have thrust bearings that can be gotten with oversized thrust dimensions--yes , if worn , a crank thrust can be welded/reground.
Rod side clearance is not a problem unless it isn't enough----there is no
oil flow on the rod journal unless the rod size is suffient to let it out--in these days of aftermarket cranks and rods, it is a vital measurement ----also it needs to let
oil sling up onto the cam and lower cylinder walls---the old days
oil squirt holes aren't in the aftermarket rods-
Looks like you will probably be pulling the engine as there's quite a bid of Alaska there( oh, California had a gold rush too)