I just installed a 7inch monitor and Blaupunkt DVD/TV in my 2005. I simply tapped into the rear of the AUX plug on the dash. I did this by stripping a set of RCA's, matching the grounds together and soldering this to the center (black) coming out of the aux. plug. And then soldering the signal wires to the appropriate wires coming out of the aux. plug. YES, it is not nearly as loud as the stereo... But in all honesty its plenty loud for me. I MAY install one of the amplifiers later, but not sure.
The most fun was taking apart the overhead bin and fiberglassing in the bezel for the monitor. It now looks like a completely stock unit. The monitor I used was a Soundstream 7 inch wide that I bought brand new for $125. The DVD/TV was on sale also for $99. Cables were another $35. And it took all of about three hours to install. I will post pics if people are interested...
The most fun was taking apart the overhead bin and fiberglassing in the bezel for the monitor. It now looks like a completely stock unit. The monitor I used was a Soundstream 7 inch wide that I bought brand new for $125. The DVD/TV was on sale also for $99. Cables were another $35. And it took all of about three hours to install. I will post pics if people are interested...