Try to shoot them with PB blaster and have the sit overnight. You could just drill the screws out?
![biggrin](http://soda-machines.com/discussions/Smileys/smc/biggrin.gif)
But yes Tim is correct there is a very small screw that secures the flapper in place in can be removed with a small allen wrench. Sounds like your screws are seized in the secure the coin mechanism cover.
Jared