I had the same question and just talked to the dealer. They said the headrests are an active part of the airbag safety system and cannot be removed.
If you will carefully press in on the backside of the material of the front seat back following a straight line downward from the headrest post you will come to a tab at the end of the post. Raise the headrest to the upmost position, press with your thumb on the material and against the tab while putting just a small amount of upward pressure on the headrest and the tab will release the post. You have to do this to both posts of the headrests to remove them from the front seats. I have an 89 240 and the headrests do come off, as do all 240 wagons.
Most headrests that have no outside release can be removed by taking a old hacksaw blade and sliding it down the headrest shaft about 4-8 inches to release the headrest. On some the catch is on the front; others on the back; you will need to try both.Extend the headrest full up then slide the blade as far down as you can, then push the headrest AND the blade down at the same time, then pull up on the headrest only holding the blade down at the same level; the headrest will pop out; if it does not, try again. I used to remove a lot of these having sold custom seat covers for years. Some can be stubborn. I hope this helps you. Mark
Hold down the small headrest adjuster release button, and then pull the headrest straight up and out.
Under the plastic rings that are around the metal posts there is a slider that holds the headrest in place. There are two ways to remove the headrest. The first method, which I think may be the "official" way to do it is to use a pin or a straightened paperclip and stick it in the small hole on the side of the plastic ring. If you push hard enough you can slide the lock enough to release the headrest. I found that the plastic clips are easily snapped off and on so I just did that and moved the slider lock with my finger. I was even able to get the headrests to lower all the way down so no metal post was showing when I put them back in. It's a simple 5 minute process.
Press the release button and raise the headrest as far as it will go. There's a small hole in the plastic base that does not have the release button. Straighten a paperclip and insert into the hole, pressing until you feel the release lever move. The headrest should lift out.
Unzip back. Remove upholstry rings on the two bottom metal rods then slide the rear one half way out to fold it up. Remove rings holding middle metal rod. Push headrest halfway down. Slide a screwdriver up the front of the headrest post to keep the release lever from closing while removing the headrest. It is located behind the front seat foam. I have a 93 Lebaron GTC Conv
Press the release button and raise the headrest as far as it will go. There's a small hole in the plastic base that does not have the release button. Straighten a paperclip and insert into the hole, pressing until you feel the release lever move. The headrest should lift out.
Press into the fabric of the seat, immediately in front of the base of the headrest. This will release the catch, and the headrest can be adjusted up or down, or removed entirely from the seat.
Headrests sometimes require removal by pushing in from the back side of the seat (in the middle area) while pulling up on the headrest. There is a release mechanism inside the seat under the upolstery. Sometimes there is a latch to supporess on the grommet where the steel shaft goes into the seat top as well.
The round plastic bushing closest to the seatbelt has a very small hole in it facing the passengers side. Lift the headrest up all the way then push a paperclip or small punch in the hole and it should lift out. You may have to press the release button on the other bushing at the same time.
There is a button at the bottom of the headrest where it goes into the seat press the head rest down as you press in the button and it will release it as you pull up
At the top of seat where the two rods of the headrest fit there is a button to push gently inward to adjust to your liking.