Previous owner mushroomed the axle out. I barely got the nut off after tapering it out with a grinder but can’t get the new nut on. Should I grind more off, kind of stuck and need to move the car

Previous owner mushroomed the axle out. I barely got the nut off after tapering it out with a grinder but can’t get the new nut on. Should I grind more off, kind of stuck and need to move the car