Removing molded detail is mainly a process. i first try to clip of as much as I can with my Xuron sprue cutter. If there is a lot of the detail still left I'll CAREFULLY grind it off with a Dremel tool on the lowest setting. Then you can tape around the area to protect the surface while sanding what remains with sucessively finer sandpaper until the area is smooth. Good files can save a lot of work here instead of sandpaper if you have them. If ,after all of that ,the area is not smooth enough, it can be polished with Novus #2 plastic polish back to the original sheen of the plastic. Good luck