Service body truck

Hello everyone, I'm not sure if this should be in "General Discussion" or maybe "Convenience and security".

But here goes. Ive got a 96' Chevy Silverado 3500 that is a service body with 7 doors.that id like to keep a few tools in.

But I'm kinda worried about the security of it. mainly at night. Ive got a camera that points directly at the truck but because of the bulkiness of the truck its kinda hard to see all doors. the truck also has a light bar on the top the yellow kind that spin around. And I'm wondering if threes an easy circuit that could be used to turn on the light bar by way of pin switches id install in each door. But I'm also thinking that id like it if when a pin switch is triggered that the light would stay on for a certain amount of time or a secret reset switch ,even if the door was quickly shut, or the person opening the door were to simply push the pin switch in with there finger to stop the light.

the reason i want such a poor man alarm is that I don't like having to sit and watch the camera feed all the time. and I'm sure that if my light bar lit up that would grab my attention and alert me that a door was opened. And the way i see it the pin switches are going to need to be installed anyway once i get a alarm installed. and id be saving the added cost of an installer putting in 7 extra door pin switches.

thanks for the forum and your help. its much appreciated.

Hell, that really is an easy circuit. Just to clarify the "roof light switch" in red at the bottom of your diagram is the existing switch right? all of the pin switches as per diagram connect to the black and white wire and it will sense the change in polarity of multiple wires?

Thanks

Also while looking over the DEI 528T paperwork, The max Amperage is 15amp . and if more is needed to use a 30amp external SPDT relay. How would that wire into the diagram. If needed that is.

thanks