I'm looking for some tips on removing the pots knobs from my amp.

I don't know how to do it.

I need to access the solder side of the board to replace some electrolytic power caps that are making the amp motor boat, and even though I unscrewed all the screws the pot knobs are still acting as screws holding the board to the chassis.

This works for most knobs:

Take an ordinary shoestring, wrap it around the under side of the knob once or twice, then lift up with the ends.
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Thanks! It worked!

Next step is to find my Craftsman wrachet set to remove the nuts that are still holding the pots to the chassis.