a buddy of mine bought a mileage out truck from the company that he works for. 06 5.9 auto 4x4, but when they took the flat bed off they just hacked it off along with the spare tire winch. is there a diagram for the back half of the truck, lights trailer plug? we are kinda rebuilding the truck a little at a time.

 

I found and downloaded the entire service manual for my 06. It is great to have and has been indispensable. The only draw back for what you are doing is the wiring is spread out over multiple pages.

 

http://www.dodge.com/bodybuilder/2006/intro.pdf
follow the link, hope it helps,