Hi John,
Against an insulator the current will not increase linearly it depends on the temp coafficient of the insulator. I was going to rerun it with the higher temp, but I had to earn my keep and run a series of models that will pretty much keep the computer busy until sometime Friday. But a semi educated guess would be probably be about 55 amp.
As far as the loading with that short of a piece it would be total current it would not have to be evenly distributed, just the input would be from one end.
Brian, to get the free space rating you need to be about the width away from anything disturbing the air flow or have forced air flow.
