I have a 2004 Discovery and would like to bypass the factory amp. Does anyone know how to do this?

 

If you download the RAVE, or look at it online in the links below the circuits manual shows wiring diagram in color, plus has connector numbers. The electrcal library has connector pin outs and color photos of their locations.

 

Here's a diagram for all of the audio system wiring you can use: 2003-2004 Land Rover Discovery with Harmon Kardon Wiring Information