Seems to me that in order to get both door jam switches and the switch at the dome light to work correctly, the switches need to be on the ground side of the circuit, with power going directly to the bulb from a constant power source. Is that right? Or do you use the door jam switches to give power and the switch at the dome light to give ground. That would make the dome switch a kill switch for the light. And why do dome lights always short out? On my 51 Chevy and my buddies 54 Chevy the dome lights sizzle. I am going to totally rewire mine... Thanks!
furthermore, if you are using original dome lights they had the power switched, if you have installed a new light switch you will need to throw in a relay to reverse polarity to the dome light. That way the ground switched jam switches will flip the power for the dome.
Yep, the dome light switch grounds out to bring the light on. You can double check that the right kind of switch is in your Jambs, it only has one wiring terminal.