Note:  Make sure you've installed all the software and made sure it's running the way you want before mounting the equipment in the car

The Power Supply

First things first, assuming that you've already removed the console cover and removed the old radio, wire DC-AC inverter to a 12V lead in your car, preferably the cigarette lighter lighter or the power leads for the stock radio.  I would suggest using the cigarette lighter if you don't use it or if you plan to leave the radio in there.  Wire some kind of SPST switch on the 12V line so that you can turn the inverter on and off.  This isn't needed if you plan to have the inverter at an easy to reach place.  I decided to hide my inverter inside the console, since the stock radio isn't there anymore, there's lots of room to hide the inverter.  The reason I wired the switch is because when you start the car, it cuts power to all the accessories and that momentary power outage is enough to trip the built in circuit breaker in the inverter.  I use the switch to turn on the inverter after the car is started.  Plug in the cables for the computer and the PC-TV converter.

The Screen

Mounting the screen is different depending on the size of the screen, where you want it and the model of your car.  Naturally, the console is wider than the width of the screen.  I've mounted my screen as far right as it will go because the power and RCA jacks are on the left side.  Now what to do with that big gap on the left side?  Those 5.25" drive bay space fillers work perfectly, just cut one to size and glue it into the console with a really strong glue.  Drill the proper holes to mount the screen and drill a hole in the space filler for the SPST switch and another for normally open push button.  The push button is wired to the computer power button.  If you're not using an ATX power supply, the push button isn't needed.  Next mount the button and the switch and wire them in.

The Speakers

While you have the console opened up, connect some extention wires to the speaker wires that originally went to the cassette deck.  If you plan to use the RCA input on your current deck, just plug some RCA cables into the inputs.  I don't suggest cutting the original connector off if you don't plan to keep your car.  I used quick splice connectors to connect my cabling, they're available at any local Radio Shack.

Close Up The Console

That should be all you need to do behind the console so just go ahead and close it up.  Make sure that you have the following cables hanging out:  Computer Power cable, Speaker cables, Video cable, LCD power cable and PC-TV converter power cable. 

Mounting The Computer

At first I was just going to mount the motherboard in the car, it's small and hard to see but then I remembered that I own a convertible car and I live in Vancouver, one of the rainiest cities in the world.  I'm not sure if the tops leak or not but I wasn't going to take any chances.  I bought the smallest tower case I can find, I couldn't find any slim desktop cases.  I removed the face plate to save some space and I installed everything inside the thing.  Everything was mounted inside except for the DVD drive, that was mounted outside the case.  I just strapped it in with my T-Top strap and I store my tops in the trunk.  I didn't want to bolt it in because I want to occasionally remove it to upload songs into it.  Make sure you mount the hard drive pointing up and perpendicular to the ground.  That way when you hit those bumpy roads, the discs don't flex and the heads don't crash.  The brand of drive is also important, try to get one with some kind of shock protection like a Quantum or even better a Maxtor.  Maxtor's shock block protection can withstand a 1000 G shock.  I think you have more to worry about than your computer if you experience a crash of that magnitude.

Connect The Computer

Start connecting your computer starting with the power cord, you want the thing grounded first or you might short something and fry some of your components.  All you need to hook up basically is the power, video, sound and keyboard/keypad.  I have some extras to plug in such as the GPS receiver, remote control, finger trackball (it's going to be replaced with a touch pad).  I also have the DVD drive mounted externally, I have an IDE cable long enough.

Connect The Amplifier

Seeing as how I don't have the cassette deck to use as a receiver anymore, all my sound will now be going through a 2 channel amplifier at 120 watts per channel.  First hook up the positive power input on the amp to the positive terminal on the battery and use a thick cable capable of carrying at least 30 amps.  Next wire the negative power input to the car body.  Now what about the remote voltage?  Easy, it's basically a 12V signal that tells the amp to power up.  There's many places where you can get a 12V line such as your ignition wire, cigarette lighter wire or I used a yellow wire from my computer, that puts out 12V.  Next connect the speakers to the amplifier, make sure you wire it left to left and right to right.  Start up the car, turn on your computer and adjust the gain on your amplifier so that you don't hear any white noise. 

Connect The Subwoofer

I just recently found a box that will fit behind the seat of my car.  The box is made for a 10" subwoofer, I'm using a Kenwood Hurricane sub along with a California Profile 2400 Amplifier that can provide it with 400 watts of chest pounding bass.  Basically, you want to branch the output from the computer to your amplifier, don't use the output from the other amp, it could blow your sub amp or create a lot of distortion.

Test This Baby Out!!

You might want to start your car first.  Turn on your computer and your video converter.  When windows has booted up, start up winamp if you didn't put it in the startup group.  Turn the volume all the way down, adjust the system volume as well.  Turn the volume of winamp a few levels up and then turn up the system volume slowly.  This step is very important.  I blew my stock speakers because my system volume was up too high.

There You Have It!

Now you have one of the best systems on the planet with an endless supply of music to listen to.  Now there's a lot of little things that still need to be done but I'm not going to get into that because every system is different.  Mine for example needed to mount the GPS receiver, the remote control receiver, install map software,  PowerDVD, etc...  Enjoy your new system!