Engine Mustang cooling and temps

Hey Guys. Foxbody temp and cooling question.
Have a 306 with HCI, 24 lb Injectors, 180 T Stat and I just installed a Fkex a lite 185 and have a year old SVE 3 Row Aluminum rad. The car when idling is fine. Fan turn in at 185 hit 187 and cool down to 177 area. When I start driving the temps start to climb hit about 200-207. Won't come down until I get to an idle and it just sitting there idling or I let off the throttle. I bled the cooling system with a Lysle Funnel and have the air out of the system. Trying to figure out what I need to look at? It's a GT so air flow is restricted a bit. The air damp plastic pieces are still there. The fan is suckling in air. The car has a Alt and Water pump underdrive pulley but stock crank pulley. Should I change out the water pump pulley?
Timing? Water pump? Not sure where to look next. Any help is appreciated
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Does it cool on the highway at a steady cruise or does it still run hot? Sounds like it could be an airflow issue if that's the case.

DO you have the radiator side deflectors in place? Are the fins on the radiator clear and free of debris?
On the highway it runs hot unless I'm off the throttle. If it's just coasting it starts to cool down. But one I'm back on the throttle it stops cooling down. I have the air reflectors on the side. The rad is clean. No debris and I flushed the whole thing
Is the air dam under the radiator in place and not busted?
It is the first that that gets hit under the car if you run over any kind of solid object.
Air damn is still there. Thinking maybe switch out water pomp and do a stock water pump pulley. It was a new T stat in April but I can change it again if need be. It's a new motor. Has been runny fine within temps. Had the first super hot day and the sve dial fans weren't doing much. Bought a flex a lite fan having same issue
Yes put the stock water pump pulley and alternator pulleys back on. More coolant flow and more alternator output can’t do anything but help your situation.
The pulley and water pump most likely won't solve it (assuming the right water pump is installed and you can see coolant moving with the radiator cap off).
At speed it should be moving plenty of coolant and it's not like water pumps break and somewhat work.
It either works or doesn't. The fans don't do much on the highway so i wouldn't be worried about the fan..

I agree with mike, pressure test it. Sounds to me like maybe somehow air is still in the system or getting back in there.