Stuck castle nut on front AND rear axle

Did you slacken the pinch bolt?

 

Have you slackened the pinch bolts at the bottom on the fork legs? If not do that and you can put the nut back on the wheel spindle a few turns and get a piece of 4 X 2 timber and put that on the nut and hit the timber with a hammer.

 

Apply penetrating oil to both ends of the axle (as mentioned earlier for the nut problem). Let it creep in for a day or two to losen up the rust. You'll probably still need to use a hardwood or brass drift to hmmer the axle out.
When you do get it out clean it up good so it's smooth and shiny again, and grease (moly grease is my preference) it up before mounting the wheel.
Inspect the wheel bearings, they might not be in good shape.

 

put something heavy/solid on the other side, otherwise the forks just flex when you hit it

 

Have you loosened up the pinch bolt on the left hand side of the wheel? If you have, then go back to the hardware store and get a taper punch about 12-14 inches long, stick it in the hole in the axel to see if you can spin the axel. Saturate the axle with P-B Blaster, bump the axle back and forth, flip the castle over and screw it on back wards, leave it even with the end of the axle so you do not mushroom the end of the axle as you strike the end; better yet get a soft faced 3 pound dead blow hammer, leave the nut on the end of the axle. As you strike the end of the axle, try to spin the shaft with the taper punch, keep the axle shaft saturated with the P-B Blaster. Just keep hitting it back and forth. It may take awhile, but it should come loose

 

Excellent idea!!!!!!

 

long way around for front wheel is to remove forks so you can get to a side of the bearing and use some penetrating oil as axle may be frozen to the spacer between bearings.

 

My 1981 XJ750UK has the spacer seized on the axle shaft - so I am letting it sit with some penetating oil overnight before I start again.
Obviously it flexes my forks sidways when I hit the axle end, I suspect I am going to have to get my son to hold the fork hard to get the jarring into the spacer.

 

Cut a 'v' in a piece of fence post for him to push on.

 

Well it worked!
Having a 185cm 100KG ( 6'2", 220 pound ) kick boxer holding the wood stopped the fork moving
Spent the weekend doing short rides bedding in brakes and new tyres and looking for other quirks.
After all, its been off the road since 2012 so I am expecting something else to need fixing during the "reanimation period"
This summer is going to be fun!

 

Result.