1979 Vermont Castings Resolute Door Clamp Screw

[Nat54]

I'm rebuilding a 1979 Vermont Castings Resolute. I need to replace the gasket around the glass and I can't remove the four clamp screws. They're rusted in. Does anyone have any suggestions? If I am able to get them out, but destroy the screw heads in the process, is there anywhere I can get replacement screws?

Thanks for any help.

 

[DAKSY]

Soak the screws in a penetrating oil like PB Blaster for a day or 2 & keep adding more every couple of hours.
Then use a hammer-type impact driver on the screws. If you break one or two ar all of them, just match the threads.
They are probably 1/4-20s

 

[Nat54]

Thanks for the help. One out, one broken, two to go.