just did a nex2300 pac and the fark is a waste if money if you are running rca's...
the chime module that the pac has is a door chime and beeps for my backup sensors i only had to cut out a very small part of the dash the old radio support
so the fark is only good for adding a sub amp to a factory stereo.
the fark don't goto the factory speaker outs it just taps in before the amp to the low signal.
here is the wire harness explained that came from the boston amp that you need to wire up the speakers colors and what they do
blue with black stripe right rear -
light blue right rear +
dark green right front -
light green right front +
gray left front -
tan left front +
blue with white stripe left rear -
dark blue left rear +
cut them and splice some wire from your 4 channel to them
now if you are color blind i can't help you LOL
do it that way and it took me 15 min and i saved 90 buck's but i have was a installer back in the 90's and i have never paid anyone to do my installs for me.your mileage may vary
https://youtu.be/jP28s8uyjVI?t=2
honestly putting it back together with the gauge pack is a pia i had to get the gauge bezel in place and not lock it down leave it loose and i had to leave the radio bezel loose if you slow the video down you will see it not real easy.almost worth paying to have done