RSE DVD bypass to Nav Screen in motion hack

[dtp]

I have a 2006 4runner with the stock RSE DVD and Nav unit. I heard from the Lexus forums that I can ground the brake wire and cut the speed sensor wire to the Nav unit and then I'd be able to get the Video from the rear DVD player to the front screen. Has anyone with a 4runner done this. I'd like my wife in the passenger seat to be able to watch the videos and help move thru the menus for my kids in the back seat.
Any tips appreciated, I'm planning to do this over the weekend if possible.

 

[dtp]

project starts in 7 hours when the kids go to sleep, any last input from anyone that's done this? i'll try to report back and let everyone know how it worked out.

 

[dtp]

well, i did the mod of grounding the brake line and putting a switch on the speed sensor, and it doesn't fully work.
video will come on if if the parking brake is off, but after 30-60 seconds of driving, the screen will switch to navigation instead of dvd. i did some more searching and it looks like i need to run a speed pulse generator to the speed sensor line. looks like parts cost about $15 at radio shack or i might be able to find a pre-made one for about $50.