Hello, my coupe seems to be overheating, I tried replacing the stat and flushing the marginal radiater but still runs too hot. I figured the fan was not coming on and upon checking the thermoswitch discovered the bottom of the radiater was only warm while the top was HOT. I decided to take the small hose to the overflow tank off to see flow and there wasn't any! any suggestions my next guess is water pump impeller bad or something any advice would be a great help. Thanks in advance!

I was having similar issues with my 4KQ. I THOROUGHLY flushed the radiator AND the engine with the hose. I then refilled with a 90% water 10% anti phosphate coolant solution with a bottle of Red Line Water Wetter and 80 DEG T Stat. It now runs between 1/2 and 5/8 from the OE coolant gauge reading.

The CGT isn't a system you can just fill with water and go.
That little bleeder fitting in the top of the rad should be done last, after 'burping' the top hose a few times to get the air out of it. Then trickle in water into the bleed hole until it's full. That should probably do it.