I reuse headliners all the time. The key is being very gentle in removing them. And knowing where they are attached. I just took a headliner from an 82 and moved it to an 81 no problems. To get it back in right usually does require removing the back glass as the headliner gets tucked under there and glued to the pinch weld. ALso agree 100% with Graham. NO URO! This was one place I used the real mercedes part. They were not expensive. I also replaced the foam seal between the pan and roof. While I had the roof out I removed all rust, por-15 and chasis coat black. IT was a total rebuild I anticipate i will get many years before i have to fix anything on it!

Having the FSM works wonders. If you plan to part this out or not restore I would clean it up and JB weld that sucker as others have said.

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1978 Mercedes 240D
1981 Mercedes 240D
1982 Mercedes 240D