85 TA 305 TPI, has a Hayden fan kit set to kick on at 210. Runs between 190-220 at all times and any weather EXCEPT going uphill for any extended time. Creeps over 230 and is heading up so Ive always just turned around back downhill, and it immediately drops back down. Weird. Any ideas? Water pump is fairly new as well.

 

This is a long shot, but you MIGHT have an air pocket that lodges itself in the back of your motor when you go up hill. I would say to jack up the rear end, take off your radiator cap, start it, and let it warm up. If the coolant level goes down, top it off.
(jacking up the rear end would cause the air pocket to shift to the front and escape)
I think it would be worth a try.