I've run across stubborn rusted parts like that in the past. If the penetrating oil does not work,(normally it take several attemps) wipe it off and try some cold. Heat usually expands the parts. Sometimes enough to crack the rust bond but sometimes not. If you go to the hardware or party store, ask for a can of CO2. Carbon dioxide. They use it to quick freeze party drinks. That will shrink the nut enough to usually loosen or snap off. Be careful though, it's extremely cold and it can burn to the touch!
I know it gets mighty cold up there. I spend a week up there many years ago at the Irving Oil company. Good Luck!
RapRap
1940 ChoppedChevyCoupe
