I bought new MB Tex covers for my 83 SL from Topsonline.com (through their eBay auction). The seat bottoms look great but I couldnt get the seat back to look right in my trial fit,....the cover appeared to be too wide at the back, so that there was a big excess of material puckering on the sides and where the sides met the center portion at the back.

I called the seller, he said that I needed to add foam padding because the horsehair pad has shrunk, or that maybe someone put SLC seats in my SL,....and that they are not identical.

The cover is actually so tight from top to bottom, that I was unable to get the bottom lock strip in place by my self, so, I had an upholstery professional look at it (for a fee). It took two of us, a heat gun and bending the metal lock strip tab out to be able to get the bottom lock strip in place. then there was WAAY too much material with puckering on both sides of the seat back just like I had noticed on my trial fit.

The Manufacturer said, he never has a problem with his SL covers unless the old pad has collapsed which would require some new foam padding, or its the wrong frame (like an SLC). The upholstery guy said he has never had an issue with the covers he uses, (GAHH), but that they are more expensive than the $399 I paid for mine (which included an arm rest, head rests and material for the backs. He further said that the padding most likely wont correct the loose from side to side problem because the seam wont line up on the back of the seat back opening,......where it needs to go.

Now wondering If I do have SLC seats. I have an orange sticker on the horsehair pad on the one seat I have taken apart,....it does have a 107.910.0516 printed on it. So far have not seen a number stamped on the metal frame.

Can anyone assist?

Brian in Austin