I have the Stewart and it works great my car never goes over 180 degrees, I have a Ron Davis Radiator, Flex fan (switching to Perma-Cool electric while the motor is out) and 195 degree thermostat. My Stewart was $69.00 for the un-polished version.
You don't need a alt upgrade to run a electric fan either, so I would go with a electric model if you can, but the stock set-up works really well from what I have been told.
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My Ride Check Out My Site 91GT, Holley SysteMAX II Kit-Heads 2.02" x 1.60",Full MAC exhaust 1-5/8" Long tubes, 2-1/2" O.R H-Pipe, 2 1/2" cat back, 12" K&N Filter, RNH PERFORMANCE Ram Air, Ron Davis Radiator, Full Suspension,3:73's, Welds, Best on new motor-12.60 @ 108, no traction 1.98