As always great information from Herman on dressing the sealing surface.
The yoke retainer is one of the undesirable points when it comes to the MK5. Unlike most other SP models, it cannot use the universal yoke retainer or DIN, so when you have an issue such as the OP's you're almost stuck with it.
I'm not a big fan of using vinegar in any concentration on regs already showing signs of compromised plating. Chrome really does not like vinegar, and vinegar does not like chrome. I know it's used and extolled by many, but something more gentle like 5-10% phosphoric acid does just as good a job (or better) and the smell is more pleasant. I'm sure there are other products equally as effective. I think Bryan uses Salt-X.
Anyway, a little elbow grease and you're MK 5 is back in business.
(Edit: Good morning Luis, I did not see you at the typewriter...er computer)
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