Trailer wiring harness diagrams W/o internet goose chase

am probing the wires on a 1500 ram slt with tow package to hookup a trailer , it appears that the trailer wiring harness runs all the way down the frame to a junction box ,the wires don't just come off the tailights like others ,what I need is a good wiring diagram that tells me what color wires are what as the tail lamps etc seem to have different colors than the truck trailer harness , I have no marker lights at all and it looks like the markers are black/yellow stripe on the tail lights , but are different on the trailer harness please help ...Internet my But ...seems like when you type something in it leads you on a useless goose chase thanxz Ben