The Vanagon brake fluid reservoir grommets seal the fluid reservoir to the master cylinder.  There are two used in all 1980-1991 vans. Note: These grommets are included with new master cylinders...

This brake fluid reservoir cap fits all master cylinder fluid reservoirs in all vans 1980-1991. Note:  The float shaft may be shorter than the one in your van. No big deal. Your low fluid...

Coolant reservoir cap for overflow bottle behind the license plate. One per Van Ref ID: 025121482 Shop by Diagram Hover over the icon and click to get the detail.