OP, it's nice of you to think about your passengers motoring experience.
I hardwired a monitor into my steering wheel.
(I know selfish right? )I just tapped into the horn wires, then I taped the horn down so that it was always on/hot...so that it could power up the monitors. Sure it was noisy with the horn masking the sound of the movies, but I found that wearing headphones to listen to the movies while driving around helped a bit.
The ideal set up would be a HUD projecting across your entire windshield, but that's a whole different thread.
Bewahren Sie ihre ultimative fahrmaschine