Does anyone know how to modify the in-dash DVD payer so that it will continue to play when the truck is not in Park?

 

look at the diagram... mine needed a ground signal to let the screen work. Mine went off the emrg brake. and then the light for the brake got a ground then the screen worked.... I then just hooked up a toggle switch and went from that wire of the dvd to the switch, then from the switch to a ground. then when I wanted to have the kids watch a dvd a flip of the switch was all it took.

 

hes exactly right, ground out the parking brake wire, whether its to a toggle switch or not

 

some you can also go into the settings of the player and change them so that the safety features are turned off.