Become a Full Member and get the official Linkage Tour and the official Starting Aid. This information alone will pay for your membership
We discussed this a while back Here ya go... https://www.sl113.org/forums/index.php?topic=25271.msg180720#msg180720
As to early 280ies, one of the Pagodentreff members has got 280 SL no. 000035,still with the factory-original two-piece hubcaps & rings ....Achim(VIN number aficionado)