I hear ya but I cant believe that a sledge won't take it off in a few whacks if we're not trying to save anything from the backing plate out.
Have you ever removed one of the tapered axle drums before?
I watched my boss, with 25 years of experience working on those tapered axle drums destroy an axle shaft trying to remove a drum once. He had all the correct equipment and he used every trick he had ever learned and it still didn't work. Sometimes they just don't come apart. He ended up cutting the drum and removing the brake shoes to get the axle out and replaced that axle with a junk yard axle shaft and drum.
I bet I could break the the whole dam end of the axle off, flange welds and all with a sledge. Those backing plate/ axle flange bolts would probably go first though. In reality that's all that has to go then the drum,axle, brakes, and backing plate all go.
I have removed tapered shafts on many tractors/machinery of much older vintage than that but not that particular joint.
To the op... impact the nut off give it a whack to back of the backing plate or two with a sledge assuming you have an impact for the nut and a 5 or 8 pound sledge. I'm not talking a hand hammer here. Give it a shot, let us know.
