Jack,

I feel your pain. I picked up two planes that had the same spinner. What a pain in the *****. The only way you will get the spinner onto the back plate is to line up the tabs and then wack the tip with a block of wood. And you have to wack it good or all the tabs may not seat into the pockets. AND, when you go to take them off you have to fit a small screw driver into some slots and pry it off which usually damages the finish.

Who ever designed this spinner had to be on drugs and should be arrested and put away! LOL

I threw mine out after several of the tabs broke off.