I have just finished adding the reclining rear seat to my '86 300SDL. This is not a job for the faint of heart, but for those who like to take the car apart (and put it back together!), it's extremely satisfying. I'm writing an article documenting what I did, so for now I'll address the points in this thread and tell a little of what I did.

The mounting tabs for the fixed seat must be removed (all five - the three big ones in the middle and the small ones on the sides). I suggest using a rotory tool, such as a Dremel with a cutting wheel rather than a full size grinder. You will want to keep the two small tabs from which the plastic/cloth liner hangs. Also, you need to cut off the center mounting bracket for the rear seat rest since that interferes with the operation of the seat.

I was able to take apart the interior of an '88 560SEL to get the mechanical parts for the seat. The surfaces are identical in all W126 chassis, save for different parts welded on. This means you will need to fabricate connections for the pivot mounts at the top, as well as the two supports for the guide rails. Also, a hint here is that you cannot use the two mounting brackets bottom of the seat (where it "clips" on) since they are too far apart and too far back from the edge.

I'll post a followup with a link to what I did. Email me directly if you have any questions. I'd love to share what I've learned.

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Casey Cooper
"From a long line of Mercedes ownership"

'86 300SDL 250K miles (Gone, but not forgotten); best diesel I have ever driven, too bad about the Achilles heel.

'81 240D 370K miles (Sold to my brother after 9 years and 150K miles of reliable driving!)

[Five other Mercedes in family clipped for less length.]