billboards where not installed at assembly plant. they were shipped in the trunk of the car for the dealer to install to keep from getting damaged during shipping. as to the maker light housing would have been painted body color from the assembly plant. there is evidently no "correct way" to install stripes, all dealers were not constant. however, IMO , the marker light housing would remain body color and simply removed for installation of billboard and the housing would help hold the stripe in place. most likely you might find evidence of the stripe on the inside of the 1/4 panel where the opening may have been "x ed out" and folded over. you may check your inside door edge also. personally I would put the billboards on anyway, awesome look.