How do i remove a spike nut?

Question:

Answers:
If you can get to the back, insert a screw in the back side of the appropriate size. Should be about twice as long as the material the nut is in is thick. Tap carefully but firmly on the head until the nut comes loose.

If you can't get to the back, insert a 1 1/2" screw from the front. Place a 1" thick piece of wood or some other material that will not scratch the surface. Rest the head of a hammer on the block and use the claw to pull the screw out, taking the nut with it.

Of course you can also use a stiff putty knife or a thin pry bar or even a thin flat blade screwdriver to work under the lip and pry it out. Start in one spot, pry a bit, then move around the crown a bit and pry some more. Continue moving around the perimeter until the nut comes loose.