ECU-Orange Box

Don't know if this is your problem or not but I had a simialar problem in my 73 sattelite years ago. May seem dumb, but have you checked the 2 wires that go to your coil, if you get those swapped around for whatever reason, you will be able to drive a bit and then it will die. Let it cool and it will restart and run until it gets hot and then it will die again. You will search all else till your blue in the face but I am almost certain this is what it sounds like is wrong with your car.