Sills.

Where can I get sill repair pieces to weld in to the front edge of both sills? Both them and the fenders dissolved over the winter, and much more than one would have expected. I have new fenders to swap in but need to do the other repairs at the same time.

The rubberized stone guard pulls away from the back side sill hole plastic plugs that then fall out allowing winter salt water to enter. This happened on both my BRM cars 3 and 5 years ago.
I fill and seal everything with urethane caulk/sealant and have oil coated for 3 or 4 years now. I will have to do it over again this year as both cars have issues as the urethane and rock guard need repair every 2 years.

let us know how you make out.

Edit, you can buy the plastic plugs from Volkswagen if needed but you need two sizes.

I need steel repair sections, once fixed I can prevent it recurring easily enough.