Awesome, that was extremely helpful accordalpine. I seem to be understanding everything a bit better now, but I am just a bit sketchy on the wiring. Your post cleared most of that up, i'm just going to continue researching so I don't mess anything up. Is there a wiring diagram anywhere for this kind of setup? (Including the component set, subs, amps, d-block, etc.)
Pretty much, you'll run the initial large wires from the battery, through the firewall, and down along the side of the car, hiding it in whatever manner you want - under the carpet, or fancier and nicer. You'll run it to wherever you mount the amplifier. From there, you'll put in the distro block, and run the short strand of wire from the block to the wire. In the future, you'll run a second strand of wire from the block to the second amplifier.
For the other wires, you'll be running the remote turn on leads, and the RCA cables. How you'll run those will depend on the car, I don't know the model well enough to tell you that. Those will come from the back of the head unit, and you'll want to run those to the amplifiers, on the other side of the car, until you get close to the amp, you'll want them at least 18 inches away from the power cables.
For the second amplifier, you'll want to make sure to have two sets of RCA cables. For the remote turn on, you can probably just split it off into two cables after running the initial one for the two amps.
The other parts you'll want to do are to run the power wires to the actual speakers - that will also depend on the model of the car, and how much work you want to do. And that won't require pulling out the HU at all. The main thing is doing two sets of RCA cables. Almost certainly, the shop will do this for you when they install the comp sets.
You can probably google up a few general diagrams of how to do it ^^ I'll check later, if I find one, I'll post it up //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
Hope this helps //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif