Radiator question

First thing I would do is install a good quality mechanical temp gauge and see what it runs at around town and on the highway. You can actually see a temp change when the thermostat opens and closes with a good mechanical gauge in the car.

The OEM temp gauge has to many variables: resistance of sender unit, poor ground of sender to head, firewall connector, instrument voltage regulator output, etc.

Some machine shops knock the old freeze plugs into the block and leave them in there. seen this many times. I hope a good shop rebuilt your motor.

The reason for the different blade count on the water pump is A/C cars need to dump more heat, but they also have different pulley setups with different pulley diameters. So run the pump your car is supposed to use.