'17 - 9 Speaker; Adding Subs - Questions

Hello all.. sorry if these questions have been answered elsewhere.. I've been looking through all the info here but either haven't found concrete answers or haven't been able to wrap my head around it.

I just got a 17 GT Premium w/ Shaker (not Pro), and I'm looking to add two subs. In my 14 V6 with base audio, I simply tapped in to the rears for a signal. In this car, it sounds like the rears have a HPF, so pulling from there would be a waste. I understand that this car has an amp in the driver foot well, and the HU itself has some processing that can be removed.

Lets start with what I've got:
2xRE SEX V2 12"
2xPPI ICE2600.1D
L2Ci

I don't intend to replace any of the existing speakers at the moment.. I'm dead broke after buying this car.

My questions are, what is the best way to get an audio signal to the amps, what should I do for the best sound, and where should I tap in for the L2Ci?

Thanks.

I simply used a LOC and tapped both the left and right signals into the right rear deck speaker. This runs into a Hifonics Brutus 2200.1 and 2x10" Alpine Type R's. It doesn't sound the greatest, but not bad at all. I listen to mostly hard rock but even hip hop sounds pretty good.

Run the power and set the ground. Wire everything up and then just attach your LOC to the rear speakers. If you don't like the sound, find another place. But doesn't sound terrible. I guess if I had some kind of equalizer I could make it sound better. But booms right now if I turn it up.

For just subs you only need a mono signal. Your rear deck speakers should be fine to tap into as they should have a full range signal sent to them and not be crossed over since they are typically your factory "subwoofers". The LC2i is an excellent LOC as I have used it in the past, and puts out a quality signal to your amp. Just make sure you set your gains properly on your amp and you should be good to go.

I caught the rear deck speaker wires under the back seat cushion, in the harness that runs under the seat. Used a PAC SNI15 to get a low level signal to run to the amp as input. Ran the power down the passenger side and out thru the AC harness grommet going thru the firewall. If you pull the passenger front fender liner you can bring that power wire right up into the battery box. Ground can be had under the rear seat, using a seat belt anchor.

No need for a LOC on a premium, in the driver's kick panel you have pre-amp line level wires. Just cut and splice some RCA cables and run those to the amp. I did it and it sounds awesome. Got the info from this post:
http://www.mustang6g.com/forums/showthread.php?t=59142