So a friend of mine gave me am old setup that he no longer uses. I attempted to set it up last night and got nowhere. I read the how to article on the install with a factory amp and just had a few questions.

1) I have a 2002 X5 with nav and no dsp. Which wires do I use for the high level imputs? I read the article and I think im supposed to use wires 5/6 and 11/12?

2) After I find these wires, do i have to tie the negative and positive into one wire then into an rca to connectit to the amp? (essentially taking 4 wires into 2)

The amp I have is a 1000w mono amp.