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

Thanks a lot! It's my buddies first Mopar and although he has a computer he can't see type too well to read it, he's got screwy eyes (color blind...can only see black and white and shades) but man can he see paint on a car! He can tell you which way the guy was holding the sprayer when the paint went on. He can see paint thickness whereas we might just the bright color! It's really strange. So anyhow, I'm doing the footwork while he does the welding! :)