Your right, remaining silent is not a crime. But I would be willing to bet that it's enough to get your ass yanked out of the car and arrested ,maybe even roughed up a bit, for not cooperating and in the cops opinion, being a dick!
Sorry, but you obviously have little knowledge the law. COULD a LEO arrest someone for our scenario? Sure. Would it be legal? Not even a little.
Merely possessing a gun is not in itself reasonable suspicion, and once LTCH is verified, Indiana Supreme court decisions have determined that the inquiry regarding the gun ends THERE.
You have rights, don't **** them away so easily.