sealants used by Porsche, 914's Options

[dmenche914]

The 914 appears to have several types of sealers applied, and maybe different ones over the year models. On a 72 914, repair is being done on the area near teh tail lights/wheel well. near the corner of the tail light where the metal some times rusts from the inside., it appear the factory used an expanding foam to fill some areas that would be dirt/water traps otherwise. The expanded foam (urathane foam is what it looks like) was then coated with a paste that sealed the foam form moisture. The paste layer appear to be brushed or spackeled on to the car, and when broken off appears like a piece of pink bondo, but it is more flexable than bondo would be. finally the top layer is painte, like the rest of the car.

What is the material they used as the layer over the expanded foam? it looks like the same stuff might have been used in seam sealing the trunks, and floors. Seam sealers at the auto paint store are much to thin and won't dry if applied too thick. This stuff on the 914 can be 1/16 inch to 1/2 inch thick

where can i get some sealer like this? What brands?

Also there appears in some areas, but not all, a black thickish coating on the steel, under the afore mentioned sealer,and paint.

Also did any of the 914 come with a factory under coating in the wheel wells, and under the rear trunk floor?

thanks