[brucepick]

I think if you put on enough grill block to get it to 200 deg F within maybe 4 miles or so, it will need the fan to keep from overheating once you get 10 miles down the road.

Does it have a belt operated radiator fan? If so, swap it out to an electric one. That will reduce air flow but the elec fan will kick in when needed.

Best way to switch it is with a temp switch in the LOWER rad hose. Set it 10-15 degrees cooler than the thermostat opening temperature and you're good to go. I experimented with every possible position and setting for a temp switch and settled on that as very workable. Then I ran into a performance car modder (Cobra!) who had done the same on his car, with never an overheating problem even with the big V8.