99 dodge caravan

I'm installing a remote start on this van. It's a directed remote start. One that works off a negative input signal in order to signal for it to start. I normally tie these into the lock wire so when you press lock twice off the factory key fob it will start the car. The problem I'm having is that the locks in this van rest at ground and their is no positive input on the brain.

I thought about using a relay and flipping the power, but I dont know how well that would work on a door lock situation(maybe I'm over thinking it)

Little help?

Wire a single pole double throw relay like this

Pin 87 and 85- ground

pin 86- to the lock leg of the actuator

pin 30- to the negative trigger input on the remote start!

Well I got the relay working and everything. I now have a second issue. The RS comes default for a 2 pulse start. I press lock twice and it starts. Press lock one more time and it shuts off. Every single time after that, the remote start only takes one pulse to start. Which means every time he locks the car it starts. I've tried resetting it and reprogamming it..Same results.

Any suggestions or words of wisdom?

Anybody? Bueller??