My cheap ass eBay special boss on my k10 was exactly the same, cured in the same way tooDecided to fix my wobbily steering wheel. It's been wobbily since I fitted the boss kit.
I blamed the cheap boss, but it turns out the steering column nut was at the end of the thread and couldn't tighten anymore allowing the boss to wiggle a little.
Anyway, two of these big bastards, M16 washers, about 2mm thick
And the problem has gone. Rock solid steering wheel. Yay!
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