I put this unit in a 06 F250 would like to have the Avic screen play the movies trhat the rear DVD is playing while Im driving for my front seat passengers. How do I do this PLEASE HELLLPPP

you will have to take spart the rear screen (if the DVD player is built in) and find the signal wires from the player to the screen and solder a set of RCA's into them, then run the RCA's into the video 1 input (also where the ipod plugs in) if the DVD player is seperate from the screen then you just need to split the video signal between the AVIC and the screen

Yeah I've done all that but still no good the unit keeps telling me that its Prohibited. What can I do now?

the AVIC keeps telling you that its prohibited? if so then you need to do the "parking brake bypass" so that you can watch movies while the truck is moving