I posted the same question in the audio/video forum but I figured it wouldn't hurt to ask the same question here.
I need help in the installation of a flipdown monitor in a 03' Expy with rear air and the wire diagram for the o.e.m radio (6 disc indash changer with 4 speaker) for installation of a FM modulator.

Do I need to lower the headliner to install the monitor? If so, how do you go about doing this?

Any info will be very helpfull.

 

I am trying to remember how I did my bosses exp. I don't think I dropped the whole headliner, but I did have to loosen the pass side. Locating the dropdown was the hardest, but I had a custom bezel so I just had to center it up and find the supports to screw too.

Check this for accuracy, it was all I could find.
DIRECTWIRE™ WIRING INFORMATION - FORD / F SERIES LIGHT DUTY / 2004 / Audio


[PRINT THIS PAGE]


Radio 12v lt. green/purple + radio harness
Radio Ground black and black/lt. green - radio harness
Radio Ignition pink/black or lt. green/yellow + radio harness
Radio Illumination lt. blue/red (dimmer) + radio harness
Factory Amp Turn-on dk. green/purple + radio harness
Notes: This is the subwoofer amplifier turn on lead. The subwoofer and amp are in the driver side rear corner of the cabin. The subwoofer speaker wires are brown/orange (+), and red/black (-) at the radio harness.
Power Antenna N/A
LF Speaker +/- orange/lt. grn - lt. blue/wht +,- radio harness
RF Speaker +/- white/lt. grn - dk. green/org +,- radio harness
LR Speaker +/- gray/lt. blue - tan/yellow +,- radio harness
RR Speaker +/- orange/red - brown/pink +,- radio harness
Immobilizer Bypass Module: Required: Yes Type: SecuriLock Part #: 556S, 556U, or 555U
Notes: Standard on all models.

 

For the wiring I ran everything on the pass side, most of it went down the a-pillar and behind the glove box. The FM modulator went to the rear quarter glass, it never sounded good, so try to use an inline modulator.

 

Yea I got a FM modulator that is inline with the fm antenna which also has a on off switch.