That's a bummer. There are places that specialize in dash repair. Usually they drill a very small hole at the end of the crack (all the way through the metal shell) to stop the crack from migrating. Then they use a heat applied polymer to repair the visible damage. A friend bought a W210 gasser, and the previous owner had mounted a cell phone holder on the front of the dash using two self tapping screws. He had it repaired at a local detail shop. Very nice job. It is a light tan dash, and the previous damage is completely undetectable. So... Call around to a few upholstery or detail shops, and keep the UV off of that dash with a sun shield and a good thick towel.

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'78 300D 310K Maple Yellow / Bamboo
'87 300D 81K Barolo Red / Safron (RIP @ 113K)
2003 E320 34K Pewter/Charcoal
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