Sunroof Beetles have drains at the front and rear corners that are connected to tubes running down the A and C pillars. When the rear section of the Beetle roof is removed, a new drain setup is required.
To maximize sunroof movement, the tube outlet must be moved 90-degrees from back-facing to B pillar facing. Surgery can be performed on the original part, but a complete re-design of the drain plug is a more elegant solution.
3D printed drain plug
The plastic drain plug snugly fits into the aluminum sunroof rail.
A revised 3D printed part incorporates two elements: a side-facing tube outlet and an end bumper to stop sunroof movement. This adds about one inch of sunroof movement by efficiently changing the tube outflow direction.
Prepare the sunroof rail by trimming along the support bolt that secures the rail to the roof substructure, and then angle forward towards the rail end; leave an extra length that will be trimmed to fit.
Trim around the rail until the 3D drain plug fits just under the support bolt.