pin outs, pin outs, pin outs... all you need is the pin outs for the accessory and you can custom wire yourself all kinds of cool stuff. My thought is that most of the wires you need (but not plug ends) are all ready there. you will just be missing what ever wires the sub and amp need. If you can read wiring diagrams it should not be to bad.
However, personally unless you really have your heart set on using the adrenalin pioneer stereo it is my opinion that you just upgrade to a aftermarket stereo because it would be just as nice or better and you would have lots of support for an easy installation. (mind you that pioneer set up is nice)
I put a really nice "system" in my car and wiring in the aftermarket stuff is almost as complicated as what you would need to do to actually install this adrenaline unit. So the actual difficulty would depend on your ability to get the wiring diagrams and if tt requires special plugs (which I believe it most certainly dose) to get those. The adrenaline unit would also retain the use of the rear remote control if I am not mistaken if that is an important consideration for you.
-Don D.