Update: One hour of freezer time followed by heating with a torch, then using the scalloped wrench with a breaker bar has proven unsuccessful. I'll wait a little while longer and see if there are any other ideas before cutting the nut off. Sending it out is likely to cost more than the upper ill likely destroy. Is there a need for these to be this tight? I have to assume that these are tighter than 80ft-lbs. Would it be unreasonable to put the impact wrench on the end of the brownells rod? I'm mostly joking.