For the last 18 months I've been designing and building my latest custom show vehicle, the '05 Honda Civic Si loaded with Sony XPLOD gear that is featured on the cover. I did all of the designing, building, engineering, wiring, fiberglass, sanding, exterior bodywork and final assembly on the car. The only part I cannot take full credit for is the amazing custom paint.
The car features a uniquely designed electronic system that includes 27 speakers, 13 TV monitors, dual CD/MP3/DVD system decks, a rear backup camera system, three subwoofers and other electronic toys and gadgets. I took a lot of care ensuring that no holes were drilled into the vehicle and not a single factory wire or Molex plug was cut. I tried to maintain the factory integrity of the car insofar as the safety features and driveability of the car were concerned. The air conditioning, airbags and seatbelts are still intact and the car is completely street-legal and driveable.
Over the next 12 months, I will show step-by-step how I built this Sony Civic, including techniques that I developed while building it, wiring schematics and pictures demonstrating the work. While I don't expect many to build a car by themselves, readers may find certain aspects helpful for their own projects. This month involves the initial design process and first building projects including the ported subwoofer box and massive amprack.
The most important thing to me is the overall plan and setup. I spent months choosing a vehicle that would benefit me the most in my project goals. After choosing a vehicle that would best serve my goal of properly displaying the Sony products in a visually stimulating atmosphere, I was ready to begin.
This brand new '05 Honda Civic Si was completely disassembled to prepare for a full widebody conversion, custom candy paint job, handmade interior and a complete Sony Xplod A/V system. | 
The first phase of the project began by photo documenting the interior of the car from every angle. This was very important because it gave a point of reference to go back and look at while the interior was designed. |  |
The factory spare tire and jack were removed, as well as the rear hatch interior panels and trim pieces. | 
All of the removed factory parts were then organized into Ziplock bags and labeled with their original location. | 
Once the complete rear interior was removed, I noted where factory wiring and rear window-wiper fluid tube were routed throughout the car. This let me view exactly how much space was available to work with in the rear of the car. |
The entire car was prepped for three layers of absorptive material to keep out unwanted heat and vibration. I chose Dynamat Extreme for this task. This side panel holds one of six 6.5" component sets that are in the car. | 
The entire floor and backseat area were treated with three layers of Dynamat Extreme. The factory seat bolt locations were then carefully cut out. | 
A piece of 0.25" angle iron was cut to serve as the base of the substructure. The angle was carefully bolted into place using factory 14mm seat bolts. |