I know its the part that holds the front wheel hub/bearings.
The upper two holts bolt to the shock tower.
the left hole bolts to the tie rod.
The 'tangs' are where the brake calipers fit.
Good thing you posted ^that; led me to the proper place in the catalog.
Name: Wheel bearing housing
Part numbers (for mid-'84 to 1993):
Cabby-Info.com -- Your online guide to VW Cabriolets/Rabbit Convertibles Old Blue's Blog -- The adventures of a 1990 Westfalia
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