G3GM 1973 to 1977 A-bodys. Chevelles, Monte Carlos, El Caminos, Laguna, 442, Cutlass, Malibu, GTO, LeMans, Century, Regal, Grand Am, Grand Prix, Sprint, Gran Sport, Can Am, Hurst-olds, and other 73-77 A-bodies
Although I've never seen one of those up close, I'm certain the skirts can be removed. Seen many full size cars with skirts removed and laying in the trunk. It's very doubtful they altered the wheel well lip so that you couldn't install moldings.
Ditto. The factory way is to not make different parts any more than absolutely necessary. Making/installing different quarters depending on whether skirts or moldings would be used would be expensive for the factory. They would have found a way to attach either to the same standard quarter lip.