A little less than a year ago, my CD player quit working, but it wasn't the end of the world because my stock audio head unit also includes a cassette player. I don't play too many cassettes these days, but I do have a portable CD player with a cassette-style adapter. I was still able to play my CD's through this adapter.
Then the cassette player died. I was down to AM/FM and whatever was on the too-short local playlists. I became really good at punching a different station upon hearing Foster The People's "Pumped Up Kicks." Did I mention I'm sick of that song?
And yes, I'm fully aware that satellite radio and an MP3 player would solve all the "problems" I have with my audio system. Hopefully those will come later.
And yes, I'm fully aware that an audio system isn't an essential part of a trail rig.
This being a daily driver as well, I like to have some say-so about what comes through the speakers. There's also something about listening to your favorite music in the backcountry that adds to the experience. Just make sure everyone else for miles around isn't forced to listen to it, too.
I found a stock head unit in the classified ads on Toyota120.com, a discussion board I joined a while back. It's a website dedicated to the Toyota 120 platform that includes the 4th- and 5th-generation 4Runner, the not-for-the-U.S. Prado, and the FJ Cruiser.
Sixty bucks for a good used stock head unit sounded good to me, so I went for it.
Then I investigated what the installation would involve. It turns out that to install the head unit, you have to start by taking your interior apart, starting with the center console!
The link above contains an excellent step-by-step documentation of the process. I ended up taking the laptop outside with me, referring to the online article many, many times while I worked.
One thing I did before getting started (and something the linked article doesn't mention) is disconnect the battery. I don't know if this is a must for this operation, but it's the best insurance I know against accidentally damaging electrical parts. Better safe than $orry, so I disconnected the battery.
In addition to an expired head unit, I also had a couple of burned-out bulbs in my HVAC control panel. This was the perfect time to replace them.