73 Dart Sport - What kind of gaskets go around the taillights?

The gaskets used on the tailights are foam, what type Im not sure, some sort of closed cell polyethlyene I think. They come attached to new lenses, which is what I used on mine. If you have none, use some type of foam, just as long as it is weatherable and closed cell, and moderate density. I put mine on with the correct foam gaskets and smeared some of that blue urethane greasy sealant on the face where it contacts the body from the inside. I cant remember the correct name of the sealant but its used for pipe flanges and its water and solvent resistant. It never hardens either, which is fine since it will be trapped in there any way. Hope this helps !