Before buying a start box for an AMT Pegasus engine, I am thinking of building one.

I would like to have a small box like the AMT USA box that is black with the three buttons (air, propane and glow). I would like to add a low pressure switch for the start and for cool down.

Question:
Where do you get the button switches from. Any part numbers?
Any low cost ways to regulate the pressure down? I once saw a regulator from Clippard Minimatic. Is it necessary to regulate the propane gas? With what?

Optionally, I would like to add a timer circuit for cool down using the low pressure. any ideas?

Thanx for you help. I promise to share what I learn.

Dave