once you remove the amp, you'll have a connector with a dozen or so wires.  the ones you need to connect are:

Large/    Small
----------------------
Green/    Black-pink
Yellow/   black-yellow
Orange/   Orange
Blue/     Light Green

Simply connect the Large Green wire to the small black-pink wire, yellow to the black-yellow, and so on.



For particular left/right speaker identification, James Lofton (Jaybird180) supplied this info for me recently.
Yellow L+
Yel/Grn L-
Green R+
Lg Orange R-
Thanks, James!


These are the same wires you unplug from the amp.  just cut them about
2-3" away from the end of the connector, so you can reconnect the amp
whenever you sell the car.  

There will still be a few wires left on the
connector (power, ground, etc)  just leave those connected to the thing,
that way you don't have to worry about loose power wires hanging around
back there.  If you want to pull the amp out permanently, just be sure
to cover all the connections with tape or shrink wrap and then zip tie
it to the rear deck or something so it doesn't hang into the trunk.

It will all seem a lot clearer when you get back there
inside the trunk.  btw, the easiest way to do this is to just grab a
handfull of butt connectors and get on your back inside the trunk. just
leave a leg hanging out so someone doesn't come along and shut you in!