Gets hot and stalls out

OK let's talk the radiator for a minute. I've seen all kinds of posts recommending different cores, tube diameters, so forth. I've got a Northern radiator (part 209625), 2 row, 1" tubes. Fan is a 6 blade steel, shrouded, mechanical with 2" spacer. I unfortunately do not know the pump or thermostat. It would seem that a non-clutched fan would cool better than a clutched fan? So a swap to a higher blade fan, hi-flow thermostat and water pump *should* see a noticeable difference?

Alrighty...I think I may have some hood clearance issues with that, but we'll see. I've got quite the parts list going! Lol

Sounds like you have the cooling equipment to do what you want so far for the most part.
Does your fan stick out of the shroud at all?
About 50 percent of the blades not inside the shroud makes a big difference in airflow.
It will still pull through the whole radiator, but more because the air has more area to exit the fan blades.
Kinda the megaphone affect.

There have been a ton of parts suggested, but I think engine timing, airflow and coolant flow should be the priorities.
The temp of the coolant coming out the bottom of the radiator is a really good thing to know.
That will tell you if the radiator is capable or not.
Some aren’t, even though new.

One would think 2 rows of one inch should do it, but there may be other issues with the design or manufacturing.

Timing light
IR heat gun
Fan position in the shroud.
Any carb insulator is better than none.
Return style filter. (Some use the old vent line if it’s still there as the return)

These items should get you well on your way.
Timing is a learning curve we can easily help you with.