Dome light door switch, 2006 F-350

I have a f350 2006 and previous owner did some rewiring which has made the vehicle security module not functioning. Have had tech work on with no success. So, I am trying to bypass the VSM and have done lights working. My issue is the door switch on the latch is reversed from what I need. Using that switch to provide a ground results in the dome light on when doors are closed and off when opened. Switch cannot be modified. Is there any way to apply a relay to revere the results of the latch function to make the dome light work the right way? ThxRick

When does it put ground on the wire? When door is open or closed? Yes you should be able to use a relay but to give you a diagram I need to know when ground is on said wire.

Ford open circuit door switches. When door is closed, switch goes to ground, when door is open you get an open circuit.

The Super Duty's have two, or three (if it's a crew cab) door trigger inputs. The switches are attached to the door latch assembly, internal, inside the door. They are notorious for failing in the door-closed (contacts closed) position. The VSM began in 01, and I'm not intimately familiar with it, but it does a lot of functions. As an aside, a common discussion on the ford truck forums is that the connector to the gauge cluster becomes loose and affects the Radio, power windows, and dome light operation. The logic for these functions are controlled by the cluster through relays contained in the central fuse / junction box. The connector becomes intermittent, and the radio and stuff doesn't work. Try smacking the dash straight down, right in the center of the cluster. That seems to be the common thing to "test" for this maladie. My truck is a 99 with the GEM, so I don't have first hand experience with the VSM, but hope this helps.