As someone who's done nothing more than spar a handful of times, I don't have any concrete advice for you. However, I would think that it would behoove you to focus on in-fighting and learning to get inside. I think that in a way your short arms could work to your benefit. Unless they're freakishly short, which I kind of doubt, I'd imagine many of your shorter opponents will try to get inside on you because you hold a height advantage over them and theoretically that could play right into your hands.