I spent about 11 hours on my car stereo this past weekend. I got two of four speakers installed! I will do the other two next weekend.
I could have paid someone to install my car audio but I wanted to make sure it was done right. I had an amplifier installed at HiFi Buys about three years ago and they not only did an awful job, they fried my existing stereo. They replaced it with an Alpine but took three days consisting of 16 hours to get it finished. When they were done, my clock no longer lit up on the dash board and there was a huge crack in the plastic behind the fold-down rear seat. You get what you pay for!
Whe I've finished the door speakers, I will replace the head unit. That shouldn't take but an hour.
Following that I will install two amplifiers. Small, inexpensive ones, of course! These will take several hours. They require lots of wires be run. It annoys me that car stereo equipment requires thicker wire than an arc welder but, according to all the newgroups and wire guage tables, it is really necessary. When I have the amps in place, I will need to build a box for my sub and get that installed as well. The box should take a day and the install only a minute and 5 seconds.
From that point forward I will be smiling every time I have to drive somewhere, everytime traffic crawls to a stop, everytime the light turns red in front of me and every time the clock tells me it is time for my commute home.