2 things:
His surface 'preparation' leaves much to be desired
but as the old paint turns 'flakey' it may be a tough problem to solve
and
the 'sponge' applicator technique may be a bit crude also.

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However...
The vinyl paint from the German source may be the diamond in the rough that redeems the video.
You never know until you find out.
Here's the data from below the video...

interior paint can be ordered from VOLICO.de - von Liebenstein Consulting - EU SHOP
and their ebay store:
http://stores.ebay.ca/volicode?_trksid=p2047675.l2563

another paint source in Australia is here
Home

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From the ytube comments:
one recommended wet sanding before painting....
(I wouldn't dot it... you could EASILY ruin the vinyl surface; pebble grain texture)

One recommended 'stripping' the entire interior and 're-coating'...
(or you could 'just' strip the console)

Here's his process description: (in Dutch

Mijn R170 SLK 320 update pagina 44 toerrit met 14 slk's - AutoWeek.nl (scroll down)

the stripper is here:
Super Afbijt - Alabastine

Pretty radical technique:











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So it looks like 4 steps AFTER stripping:

1. Prep cleaner
2. Primer
3. Paint color
4. Top coat

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If anyone contacts/dialogs w/ the paint vendor
regarding color matching SLK to XF interiors... please post what you find.
Colors mentioned in the video were
anthracite grey found here: Super Afbijt - Alabastine

Cheers.
G.