>>>*Lots of questions, I will offer my poor opinion.

On cleaning the bolt holes, a tap should never be used as they will normally remove metal. We use a hacksaw and cut a grove vertically in the threads of an old bolt, this makes a perfect thread chaser.

If using any kind of abrasive pad on a sealing surface, be sure to go very lightly. Areas such as between the cylinders and around coolant passages are easy to erode too much metal, it takes only very little to make a mess. If you can find the non-abrasive type pads you will be better off, they clean but don't remove metal easily.

By all means relube the cam journals. The cam should rotate easily with simple finger pressure when it is correct. It can take a couple of minutes for cold oil to reach the top end at startup. Lube the lobes, too, the exhaust side gets oil last which is why we sometimes see early lobe failures but just on the exhaust side.

The only places sealant is required is areas where two gaskets join, like where the timing cover gasket meets the head gasket. A thin bead the lize of a pencil lead is plenty, too.

I would take that pan off right now and clean it out, otherwise the risk is particles can get drawn into the system, things like the tensioner are sensitive to debris.

This is a fairly easy job, just take your time and use a torque wrench, proper clamping forces are very important....*EB