I got a 3 row radiator. Ran hot, 230 at red lights. I got a new water pump (two) and adjusted the impeller closer to the pump body to close the gap, improves flow they say. Ran hot at red lights. I installed a pusher electric fan in front of the radiator. It still ran hot at idle. As soon as you give it 1200 rpms, temps drop down to normal. Never a problem while cruising at any speed. I did this, i did that, tried timing, mixture, all kinds of things... nothing made a difference. Not severely hot, but just too warm for my liking. Many people said the temp sensor just gets heat soaked near the exhaust port and not to worry about it.

I worried about it. Nothing made a damn bit of difference, it seemed like it was just not flowing enough water at idle, to cool it.

Then I got an aftermarket high-flow thermostat, 180 degree, and it shaved a good 20-30 F from my idle temperature, and even cruising temperatures dropped a little. VERY happy, for me the thermostat was the key. Next step was going to be a high flow pump, but I think I'm done now.

My t-stat is a mrgasket brand but there are others. The body is clearly different looking.

Here's one:

http://www.summitracing.com/parts/mil-16401?seid=srese1&gclid=COvgxMOoq8wCFYwfhgodjAMM1A

not sure its the right part for yours but you get the idea.

I think I have the same cam as yours, 9.5:1 CR and for now, a stock single barrel. Will soon adapt a 2bbl to see if it makes a big difference, then headers.