Im pretty sure you can apply to obtain your rights back. I know as a Felon, there are 3 ways to obtain a CHL. Expungement, lowering felony to misdemeanor, and you can also apply to regain your rights. The only thing stopping someone from regaining their rights to bare arms, i believe is if they have prior weapons charges involving a Handgun or switchblade knife. Also i believe sex crimes fall in their somewhere as well.
Mark is right though. The best way to do this is to ask a lawyer that specializes in the 2nd amendment.