I've been pounding my head (and forearms) all day trying to get this stub axle out to replace the wheel bearings. I've tried beating it, I've tried heating it but nothing seems to work. The other side popped out after a few whacks from the slide hammer but no luck on the other side. Anyone have any tips or tricks to get this thing out?

My friend replaced the wheel bearings in my 260Z a few years back. The right side didn't budge until I was hitting it with a slide hammer while he was on the other side with an air hammer. Sometimes they are just that stubborn.

More heat?  Make sure the heat is focused on the parts that need to expand.  The casting that holds the outer race or the bearing inner race.  Not the axle shaft.

Looking at the drawing, a torch flame on the casting/housing is your best bet.  Inner and outer so the bearing races get hot too.  If the grease isn't smoking there's room for more heat.

You could also use  some  Freeze..  it's a spraycan and use that on the inner parts like the axle itself and the nut.

It cools under -40 celcius so spray it on the axle..  NOT on your fingers!  You could also get the unit off the car and freeze it first in a freezer before you heat the housing of the bearing(s).