Very 6.9 SLS valves look completely different. They are shaped like cubes. I know that they are rebuildable because there is a shop in NY that rebuilds these and the 6.3 valves. I don't know how easy they are to rebuild though. Dan but if you want to take a stab, i'm quite happy to provide a spare valve and a 6.9 for the purpose of that experiment :-)

Euro W126's with full SLS share the same valves shocks and rear accumulators as the 6.9. W126 cars with only rear SLS have a different set up.

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With best regards

Al