Step 1: First find a schematic for your paticular radio.
The first thing is to remove your radio from the car. In my case, there are two holes on each side of the radio. You have to put a stiff wire, like a coat hanger in the two holes on one side, push hard to release. Then release the other side. There is no good way to get a hold of the radio. I just stuck my fingers in the cassette opening and pulled.
This is the hardest part of the whole project.
Then I made a simple drawing of the wires on the car side of the plug going into the radio. (Sorry for the fuzzy pics I didn't have my good camera.)
Step 2: Taking it apart.
Next there is a screw with a 3/16th head you have to remove. Twist this switch and it comes right out. Then pull off this metal cover.
Step 3: Step3
Step 4: Finding the solder point.
Take a pair of headphones and cut them close to the earbud end. Any old pair will work.
I had these just lying around. Just strip it back, take the wire ends and solder one to the positive and one to the negative on the back of the circuit board.
Step 5: Do it all in reverse.
Plug in your Ipod,or other Mp3 player, CD player, or anything else with a headphone jack.
Pop in a tape. I used an old weight loss tape. You won't be able to hear the tape unless you turn the volume way down. I suggest turning up you Ipod no more than 2/3 of the way, and then use your car stereo to do everything else.
You can adjust your volume, fader, balance, bass, treble on the radio itself. If you want to go back to your radio all you have to do is leave the tape in and push the FM button. It's that simple.