1985 Chevy Corvette poor performance when warmed-up

The blue smoke is most likely bad valve seals, they leak while its cold into the cylinders. I would definitely suggest replacing your pcv to begin with. The pcv allows the crankcase to ventilate, without ventilation seals with blow. The oil leaking into the cylinders, then into the exhaust is probably the reason your egr went bad. The egr valve will only affect the computer when the engine coolant temp has reached 176 deg F

As for running hot that could be a number of issues, begin cheap and go to the more expensive stuff(thermostat, coolant temp switches, then water pump) WHATEVER you do, DO NOT remove the thermostat and run it. GM engineers worked hard to make the corvette temp stay right about 205 deg F, thats why your fans run nearly constantly.

I hope this helps.

Thanks for your input.
I suspected the valve guides as well.
I'm going to make sure the EGR is working first.
Trouble is there is so many things in the way on this car but with this hood, work is easy.