Transferring image from drivers side to pass side


In Runtime
Forgive me for my ignorance because I know that there is a way to do this. I have worked with Photoshop for over 10 years now and I should know this. But... how do you transfer an image from one side of a vehicle to the other? I tried using the EDIT, Transform, and Flip functions but those make my text in the graphic either upside down or backwards.

What I am attempting to do is take a photo of the drivers side of a racecar and insert it into a racecar paint template for rFactor. It worked perfectly for the driver's side because the original picture was taken of the driver's side. I do not have a picture of the passenger side to simply do what I did for the driver's side.
So I want to take that driver's side graphic (containing a number, background graphics and some sponsorship logos) and put it to the passenger side.

Any thoughts? Thanks