New aftermarket stereo and stock amp?

Question

what do i need to connect the stock amp powering the speakers and stock sub in my 2000 lincoln navigator to my new aftermarket stereo? it has 3 sets of pre amp outputs( the stereo)

Answer 1

Not to sure, I have never wired the stock amp to an aftermarket stereo. Kind of defeats the purpose to me. But any local audio shop should know to do it. There has to be a way.