2005 F150 Sepercrew cab STOCK stereo help

[deagle50ae]

hello there.

I'm about to take on a project on my dad's new f150.

im installing a sub and all new speakers as well as two amps (mono and 4ch) and I was wondering how to do this on the stock harness...

I'm not sure if it's amplified (externally) from the factory or not and im not 100% on how im going to get the signal from the h/u to the amps. does anybody know or have a diagram of the wiring? or do you know where i can go?

I can always run high level inputs from the factory speaker wires to the amp,a nd then back to the speakers but that will be a PITA.

any hep is greatly epreciated!