72 Demon A/C conrol panel removal advice?

Hi Folks.

I have a '72 Demon 318 auto with A/C.
The heater and a/c are currently none operational.
If I touch any of the 5 buttons that control it's operation they will just dissapear into the dash. I gather that I need to either source a repalcement vacuum switch or repair what I have.

Could someone please advice me on the best way to gain access and remove this switch, please.

I've hopefully attached a picture of what I have at the end of this message...

Thanks in advance,

Jon.