I already removed mine.... Could of made a manual, should have included photos, would have...
Idk, maybe I will go install it and remove it take detailed pictures and make a guide. I can tell you to start off by removing the felt covered door seals from the vehicle body. Then remove the b-pillars, c-pillars, rear headliner, front head liner cover, grab straps.
To remove C-Pillars:
Remove rear seat, bottom cushion should have two orange/red tabs under the leg area, push those inwards while lifting up on the front of the seat. Now you need to remove the back; two nuts on the bottom of the rear back, should be by the seat belt mounting brackets.
Now remove that rear by pulling at the bottom while pushing the back upwards.
Next you will need to remove the two screws that hold the C-Pillars, they are located on the C-Pillar cover (head size is 1/4" Philips, zinc plated).
To remove Rear Head Liner Cover:
Remove center courtesy light with a screw driver, next disconnect it and unscrew the headliner cover retaining clip.
Now remove the headliner by gently pushing towards the rear window if it doesn't want to move try gently pulling it towards the front window.
To remove the B-Pillars:
Move front seats forwards.
Using a phillips head screw driver remove the two b-pillar cover trim screws located at the bottom of the cover. Next you will want to retract the seat belts a little and then grab the bottom of the B-Pillar and pull a little towards your body then push downward gently.
Remove the grab straps:
Remove covers of the ends of grab bars, each bar is located at head level of each door opening. The two covers are just pushing on, use a small flat head screw driver and wedge under the bottom edge of the cover. Then remove the screws located on both sides of each grab bar.
To remove the front Headliner Cover:
Remove center console light, remove sun visors, remove chrome screws and chrome trim strip that is located at the front edge of the sun roof opening. Next remove the sun visor clips (open up center cover to the clips and use phillips screw driver to remove screw).
Remove two retaining clips that clip the headliner fabric and front headliner cover fabric to the lip of the seal retainer (where that door seal clips on) The clips that hold these pieces of fabric are yellow.
Now to remove the headliner:
Around the entire edge of the headliner are little black pushing pins. About 3/16" diameter head. One or two under the top of the B-Pillar Area on both sides, two at the rear where the rear headliner cover was and again both sides. Remove the ones at the front that were under the front headliner cover.
Next you want to remove the headliner from the door opening edge, the headliner has a black C-Channel affixed to it, you just pull the retainer towards you and then pull down. Do this around all of the door openings.
Now you need to remove the black plastic stretch clips, located between the sunroof unit and the roof of the body chassis, they are 1/2" wide, 3" long, black. Look like stirring sticks. Located along the edge of the sun roof unit.
Next remove the headliner from the rear of the body by pulling the headliner edge towards the rear off of the retaining cut outs on the body roof. Then you need to remove the headliner from the sunroof assembly. To do this you need to be careful. This portion of the headliner is held on by means of a small steal bar that engages into a channel in the sunroof assembly. It is covered by white fabric. Just go in with your fingers and gently remove the retaining rod from the channel by grabbing hold of a portion and pull it towards the rear of the car, you will need to do this a few times along the rear of the sunroof assembly and If my memory is correct I think the rear of the body chassis as mentioned before.
I did this many months ago and I am working off of memory, but I believe this is everything. Not very hard to remove the headliner, you just need to be careful not to damage anything... Which is hard in a old dried out beauty like these.
Good luck. If you need photos or have questions I am always able to provide.
This may help too, just remembered I had this floating around in my favs.
http://www.elitegites.net/mercedes_w126_manual/chassis/68-430.pdf