Don..I cannot answer you on that as I am not the one who rebuilt it.
Lonnie...I do have steel Mani Caps. If that's what you are refering to..
Could the Pump be modified too much that's causing the Converter to push hard against the Crank with too much Oil Pressure?
Obviously, a bad main cap alignment should be checked for.
Yes. There are some pump mods that can increase converter feed flow and hence pressure builup in the T/C. Excessive pressure in the T/C will cause excessive push on the crank thrust surface, causing it to overheat. Teeing into the 'out' cooler line close to the transmission will give you a good clue as to what the T/C charge pressure is. This check absolutely should be done.
Don't use any restrictor fittings in the cooler system.
Get with your tranny builder and have him trace down the mod that may be increasing flow to the T/C. Reverse the mod. A very common mod is done to the second land of the PR valve. It is commonly overdone and allows an unnecessary amount of converter feed flow. If your using an aftermarket PR valve, study it very carefully to determine if the design may be increasing T/C flow. If there is any chance of that, replace it with an OEM valve.