Last week I removed the stock radiator from my 1993 ZR-1 with 97,000 miles. It looked like Ryan's picture. I replaced the radiator with a Ron Davis unit. I replaced just the radiator. I kept the same thermostat and the same Haibeck chip.
Since I have owned the car, I have had problems with temperatures running high and it always worried me that if I got stuck in stop-and-go traffic I would have a problem. Also, I could not enter parades because the car might over heat.
Yesterday I gave my new radiator a test. I drove around Washington, DC for an hour in 93 degree heat. (Not FL or AZ weather yet, but up there for MD in April).
In an hour of city traffic, the engine temp was rock steady at 201 degrees. I was VERY pleased. I can enjoy my Z without worrying.
Jim