I am having a similar problem with my 1971 280 SE 3.5. Once the temperature gets above 180F (which it does on a hot day in Adelaide with the a/c on) the car will not restart after stopping until the temp drops to about 175 F. Then it starts and runs perfectly normally. If I remove the fuel pump fuse the car starts and runs for a few seconds until I put the fuse back in again and then the engine stalls. Sensor II is showing the correct resistance. I suspect a fuel pressure problem. I've checked the fuel pressure at 175F and it's 30psi when the car is running. I have yet to test the fuel pressure when the car is refusing to start, but I am starting to think that it might be that the fuel pressure is too high or too low. Is the fuel pressure regulator likely to be affected by heat?

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Alastair from South Australia
1971 280 SE 3.5
1981 300D
1980 300D