2007 dodge ram with 7 infinity radio

Wiring Diagram for 2007 Dodge Ram infinity radio with 6 disc MP3 Changer  and factory Sirrus. 

Im adding a Kicker 300.1 mono sub amp to power 2 kicker subs in a Fox Acoustics box under the rear seat.  Is there a plug in my factory infinity amp to add an amp and sub.  I know that Mopar has the option available to add a factory sub.

What are the crossover frequencys for the amps outputs?

What are the RMS or watts output for the amp to each speaker?

I planned on just splicing in at the front door speakers to my amps High level inputs.

thanks

2007 Dodge Ram Quad Cab

I forgot there are different  cab makes

thanks

Here is a link to the Dodge Repair Manual for 2006. 

www.hemitruckclub.com has 2003-2006 manuals  and OE part number guides 2003-2006.

http://www.hemitruckclub.com/Manuals/2006-DR.zip

180mb zip file.