Quote.........My aluminum fan had quite a few holes over the years, which I "fixed" with bars leak. I changed out the old two core for a new 3 core and larger fan.


On the way home, there was a good sized BOOM along with a lot of smoke. The motor shut off. I finally got it restarted (in the dark) and got to the nearest gas station. I saw the distributor was not completely down. I assumed that was the problem, fixed it, and got home. I usually run around 190 degrees, but it started running hot.

Not trying to beat up on you but not one of these statements makes a dang bit of sense. No way did you fix an aluminum fan with Bars leak ?????
With the boom did the smoke come from under the hood ????
Where was the temp before the Boom ???
Where was the oil pressure at????? Because if the distributer was not seated as you state then it could not be engaged into the oil pump !!!!!
Although your statements make no sense to me heres my take on your overheating at speed. Radiator could be partially clogged, to test take a digital temp gun with the engine warmed up fully and take temp readings all across the radiator core,they should be fairly even, If it shows colder at bottom of core it usually means its a clogged radiator. Or as stated you could have a lower radiator hose sucking shut,it should have a wire spring in it to prevent that. Or is the electric fan moving air in the right direction ??? it should be blowing the air towards the engine bay depending on wich side of the radiator its mounted and if its a pusher or puller fan. I,ve found them mounted backwards and I.ve found them wired wrong so that they where running backwards,regardless it has to move the air towards the engine.
Hope this helps you.