since nobody else has said anything let me be the first to point out a few things.
1. the rule is 1 farad per 1000 watts of power, your running 600 watts 1, 1 farad cap will be more than enough, and you may not even need that depending on your electrical system.
2. simply buying the most expensive kit is not the answer, you can throw money at a problem and make it worse.
Here is what i would do, first sit down and figure out how much thump you want, how much you want to spend to get that thump and what you expect it to cost in the long run I.E alternator, battery etc.
Sounds like you've done alot of this already, next the subs you want, sit down and figure out the required airspace for these subs, cavaliers have very limited room in the back, if your running 12s you can squeeze a 40 inch wide box if i remember correctly, if your running a 15 you cant go wider than 36 inches wihtout some serious mods to the trunk, my last sub box was 36"x16.5"x10" these are outside dimensions and is absolutly as big as you will squeeze in the trunk of a cavalier without having to cut the supports for your trunk lid to make room.
now that you've figured out your airspace and needs. lets start planning this out to complete the system. you can do this one of 2 ways.
1. you can run an 8ga power wire to the 4 channel amp and a 4ga power wire to the mono amp.
2. you can run a 0 or probably a 2 ga power wire to a common fused output in your trunk, then run a power wire to your 4 channel amp, and another one to your mono amp, again 4 ga to the mono and 8ga to the 4 channel should be the smallest sizes that you run.
Wiring gauge such as 4ga is the thickness of the wire, smaller number equals a larger wire.
Now that you've figure that out you must ground BOTH amps to the same spot be it in the trunk or in the car they both need a common ground spot within a few inches of each other and ideally both grounded at the same spot or you will get ground loop noise, which is almost as bad as static.
if you go the route of running 2 seperate wires it will be messy and alot harder to do, if you run one single power wire it will be cleaner and easier to hide.
You will need a sidepost battery adapter which is a thread in replacement for your batteries positive bolt that has an extended pole on top to mount the extra power wires to.
you need at least 2 crimp on ring terminals for each of your power wires, one for the battery or ground side and one for the amp side, if you run a cap you will need 2 more for the positive side.
next you will need at least 25 feet of positive wire to run from the battery to the trunk, this allows you room to route the wire around and under things to hide it very well, which makes for a nice clean install, try to keep the wire in the car as it has less chance of getting damaged.
you will also need at least 4 feet of ground wire, try to keep the ground as close to the amp as possible and mount the amps so they get good airflow, amps get very hot, so sticking them under seats, or behind your rear seat between the back of the box and the seat is a bad idea, they will get hot enough to thermally shut down and ruin your day.
you will also need a fuse holder and fuse for your power wire mounted as close to the battery as physically possible, you will have to cut your power wire at this point and attatch the fuse holder inline, this prevents the wire from shorting out in the car and causing a fire, i prefer agu style fuse holders as they are nice and strong, hold large amp loads and are cheaper than anl, dont get cheap on these parts they will save your car.
If you run one big wire you must buy a fused distribution block, again dont get cheap.
buy wire loom the size of your power wire, 4ga wire will fit in 1/2" wire loom and should be used thruout the engine compartment up to the point the wire goes thru the firewall of the car. thats another good area to cover,
putting the power wire thru the firewall:
First get a coat hanger and some good tape, now lay down on your floor board under the drivers side of the dash, look around with a flashlight for any big rubber opening or boot thats under there, anywhere you think you can pass something thru, you do not want this wire against a metal surface, it will rub thru and ground out to the car and cause all kinds of problems. Now form the coat hanger into a long straight rod with a handle at one end, push this thru the rubber boot in the firewall, you can either wrap the end of the coat hanger over the wire and tape it, or just tape it whichever works better for you. This will save you alot of time by using the coat hanger to get into hard to reach areas.
you will need speaker wire as well, i always use 12ga wire as its a nice free flowing cable but you can use smaller wire 14ga usually works just fine.
you may need connectors for your speaker wire, you might not, your amp will either have a round hole for the wire to go into or it will have a screw that holds a flat plate down, if its the kind with the screw you need connectors, 2 per section of wire ran to the amps.
do not forget sound deadner, I've heard very good things about Fatmat, you can find it on ebay very cheap, its better than dynamat, and alot cheaper. this will effectivly increase the output of your system at a fraction of the cost of an upgrade.
If you have power problems once its installed, like your lights dim or your system shuts off research an upgrade called THE BIG 3 it involves getting more voltage to the battery from the alternator, also this may be the time to upgrade your battery, when i switched from the factory gm battery to an optima redtop my system got louder.
You also must tune your system, invest in a good tester cd that has frequency tracks, you can use lower frequencies such as 40 and 50hz to tune the gain on your amp, you do not want to turn your gain more than half way up on most amps or it WILL blow your subs. www.the12volt.com has alot more info on these kinds of things and is a great resource, as it also has calculators to figure out box size and air space etc.
and my final little recommendation is to check out a website called Sonicelectronix.com they have some of the best prices on audio gear, are very helpful, ship fast and are authorized dealers for kicker,audiobahn,ma audio and bunch of others, they also tend to run at least 20 dollars cheaper on their gear and the shipping is reasonable.
Hopefully some of that is helpful
J~
