I'm not sure how popular it was. Most people see undercoating on a restored car as being there to cover up rust...not because it originally came with it. As rusty as my car was, the floor pans were in really good shape. I'm sure the undercoating is what saved it.
When you ordered the undercoating, you also got underhood insulation. The undercoating package was designed as a sound deadening option more than anything else.
It is a very rough and hard textured sparyed on black material. You will see it on the inside fender areas, rear wheel wells, frame rails, floor pan underside, and inside the trunk areas on the quarter panels. Depending on the location like inside the trunk areas it could be painted body color.
Ok, so mine has all of that it is even painted the body color in the trunk, car is not original color but I can see if original color is under the last paint job??? I am currently getting ready to have my car painted ( I would love to do it myself but i have never painted before and I don't think I could be 100% happy with a paint job I did since I would know EVERY imperfection). Is this something I should leave on? I can take pics and post if anyone can confirm its from the factory???