[bret a ewing]

Same issue with a '66 corvette with original Kelsey Hayes. Tried penetrating oils, heating, cooling with CO2 and the spinner adapter tool with no success.
What worked:

With someone in the car holding foot to brake pedal we jacked up the frozen wheel by the spinner. Yep that is correct, lifting (racing jack with thick padding) on the correct "off" ear set at just below parallel. Then with a BMF lead hammer hit the opposite ear in the "off" direction. Nice it is always hitting down.
Even this took multiple hits to break loose but better than the last resort..........the die grinder.
Good luck,
Bret.