It depends on a lot of things. If the plastic has ever been treated with armor all or any conditioner like that, the film will have a hard time sticking. I used to manufacture dash kits and we used 3M tape. With some cars, it was just a fight to get the kits to stick when we were doing installs. Normally they say to use rubbing alcohol, but sometimes even that wouldn't clean it up enough. We resorted to using acetone on some dashes if there was a lot of residue. The primer helps, but it's not a total cure.