I've put cloth down to protect the top of the gtr, and pried them off by carefully rocking a spoon under the edge, while turning the knob so the pressure works around the knob & doesn't crack it.
It should slowly come off.
Came across an old pic, some gtrs I've sold & some I still have. I'd be lying if I said I didn't miss a few. Should have kept the Hiwatt 50w stack & the AC30 too.
No regrets, really.
I do regret NOT buying a black '57 strat that was laying on the floor in an open case, when I walked into a music store one time. I ordered a new one instead, lol