Thanks for all of the good suggestions folks. I'll let ya'll know what I find out.

 

Replaced the radiator and that seems to have fixed it. Overall running temp registers slightly lower than before (when it wasn't running hot), but none of the issues with heat soak like before when I park it for a few minutes.

I say all of this having run it on the coolest day that we've had in 6 months, and I haven't run the AC with the new radiator, but I think this has got it.

Thanks again.

next is the cruise control and ABS in that order.

 

Even on a perfect cooling system it's not unusual for the temp be 210-230 after a 5 minute stop but should rapidly come down as soon as the water and air flow are restored. Glad you got it fixed and keep an eye out for loss of coolant..next project could be the LIM. I'd love to know exactly what percentage of Blazers have had the intake gasket replaced..just seems like almost everyone here has had to do it.