I’ve changed the water pump, thermostat,
and made sure all the hoses, fans, and
radiator are in tact, but the right side runs hot
when gage says it is overheating while the
left side of the radiator is still cool.
Radiator has an internal restriction, you can use a laser heat sensing gun and scan the radiator and locate where it shows cold to verify. Might be cheaper to replace the radiator than having it re-cored or rodded out.
Unless you know a skilled radiator shop to re-core or otherwise fix your unit, buy a new radiator. Not cheap but neither is fixing the old one.