Thanks for everyone's input on this! Griffin seems to pop-up the most and is the one recommended by people that I've met at car shows. One builder had an over-heating problem, switched to a Griffin radiator, runs 180* all day long.

One concern with a radiator made of aluminium is with the brackets for the grill shell and radiator supports fracturing due to vibrations over time.

I want to run the internal tranny cooler, I think it would be more effective in front instead of underneath the car.