wolf!

Ladies and gents,
The tan (I think M-B calls it Mussel) headliner of my 230 slk 2002 had distorted, due to the lock hydraulic cylinders leaking oil all over the back. This made the vinyl all rippled around the edges, and very unsightly. This is different than the old GM sagging headliner which is due to poor glue. It looks like someone had put many rows of 1/8 inch rods parallel, under the vinyl and was not unusually loose to touch, which would be the case in glue failure. Instead, it appears that the oil distorted the foam backing.After fixing the cylinder, (look for my posts on that) I tried many things to restore it, heat, sun, solvents, cold, alternating hot and cold. None of that worked. I inquired of replacement headliner material, and was told stock material, or copy of stock material wasn't available. Also that even if i were to find it, the glue wouldn't stick, due to oil saturation. The vendor just happened to have the last headliner assembly in the country, in my color. for a few hundred dollars. Buying material, or even paint to match, is always a gamble for color. Since M-B offers a sueded headliner option in some models, I thought I could convincingly use a sueded material. this would be an advantage since a- due to texture, a slight mismatch of color would be forgiven, also, it would be more forgiving if the board was...suboptimal.
I got it in a 'sand' color from a seller named global upholstery on e-bay. for $20, plus $13.50 shipping. I only needed 1 yard, it had the requisite 1/8 inch foam backing. I also needed 1 can of 3M 38808 Headliner and Fabric Adhesive , foam amazon for about $13.50. I also had some other super 77 spray glue around, but 3M said it would not hold up to rooftop temperatures. unfortunately it was not available locally. the earlier version was, but 3M advised against using it as they reformulated due to it seeping through the fabric.
The idea of the hydraulic fluid interfering with the glue bothered me, even though I'd , intentionally, left my headliner out in the rain and temps up to 100 degrees all summer. I thought that would shrink it and help (it didn't) or at least flush out the fluid. I also cleaned under the saturated areas with generic degreaser a few times. it tolerated this well. I removed the liner from the board and my final attempt using spray carb cleaner it did not tolerate. this separated the parchment 'skin' off the body of the headliner board , and i do not recommend. It was a PITA to get back on. It did tolerate a pretty good flushing with denatured alcohol.
After pulling the vinyl off the board I sanded off the foam with 80 grit paper by hand. Then removed any remaining residue with denatured alcohol. I let it dry overnight.
I laid the material on the board to contour and cut with plenty of overlap. Then sprayed 3 coats, as per the can, on the surface of the headliner board (and an inch or so of the back of it) and the back of the material. waited about 10-15 minutes (5-60 as per the can). I then folded the material, unglued suede face together, glue foam side out, with the fold separating the imaginary driver and passenger areas. leaving overlap, pretty much as measured, i lightly touched and stretched slightly the 2 corners of the drivers side. then I stretch slightly the fabric the the passenger side, so that the material was tense enough to barely, if at all touch anything but the outside edges. this stretch is to allow the material in the inside corners not fold, and lie smooth. working from the center, circling out I pressed the material onto the board, then the inside corners before the edges. after the surface was done, i flipped it over (lie some clean towels for this, as not to dirty your nice new fabric) and overlapped the edges, cutting V notches where the corners were, inside and outside ones, to relieve strain, and reduce bulk. I trimmed the overlap about 3/8 inch. poke 3 screw holes, and cut an x where the hole for the plug to access the emergency operation key goes. I let it sit overnight. i do not believe in rushing adhesives. Then put it back the same way I got it off in reverse . I had cleaned the 3 edge moldings while I had it out, noting their color wasn't perfect either, due to sun fade. The fabric is a bit off in color, which, as predicted the sueded fabric made acceptable. it may even fade to match, for all i know. it's a tad on the pink tint. I think it looks more luxurious than the vinyl . it may be harder to clean, I'd use afta, dry cleaning fluid, on a cloth, not getting the fabric wet, or it may hurt the glue. It could be done, with care and taking one's time in 2 evenings, not including removal and reinstallation. but for trying to remove the oil.
I don't know how it will hold up over time yet.

I was tempted to use blue sueded material, to match the car if i couldn't get a near match, and also do the 3 moldings, the innermost panel of the door panel, and lower dash, where the touch sensitive paint is. but i am too lazy.
Disclaimer: this is what i did, i'm not telling you to do it, and I am often considered a poor role model.
BTW removal and reinstall: three screws in the front, 2 on each side in the moldings, look up, and it slides out of the rear molding. Of course I tell you this aftet you have finished, to make sure you read it in it's entirity before embarking on this task ;'). Don't drop or bend it or the board may distort or crease, and possibly marr your results.