In regard to the second question, it was my understanding that the only way to carry a long gun on a MC is OC... just make sure it's unloaded. I've seen it several times around the Lehigh Valley, and I've heard from a friend that that is the recommendation of the police to do that, for what it's worth.
But, using the proper definition, you cannot carry an "assault rifle" in public anyway, since by definition it is a selective-fire carbine, and would thus fall under the Class 3 category. However, you probably confused the term with "assault weapon", the term that in its current usage is used and exploited by the anti-gun crowd to eliminate all guns that they consider to look scary. If it was an honest mistake, I understand, given all the anti-gun BS spewed by the media. But if you feel that "assault rifle" or "assault weapon" is an appropriate way to describe your AR-15, please read my tirade:
The "assault" descriptive is used to assume that the only purpose you have for your AR-15 is to "assault" schoolyards full of children with it. A further point of concern with this term is that it is used to confuse the general public into believing that the firearms covered under the Assault Weapons Ban are automatic firearms when, in fact, they are semi-automatic. The sheeple imagine you going into a gun store, asking for an "assault weapon", and then walking out 30 minutes later and firing hundreds of rounds from a belt-fed machine gun into the nearest elementary school. To the sheeple, surely the good politicians must ban all guns that look scary, because all guns that look scary but be used for evil purposes, they conclude.
To me at least, and I'm sure this isn't viewed the same way by most pro-gun people, the term "assault weapon" is severely offensive. I feel it's kind of like the "n*gger" of firearms vocabulary; it is a term that symbolizes the oppression of gun owners and represents systematic discrimination against anyone who wishes to purchase a gun that doesn't have a 28" barrel with a wooden stock.
A long rifle is a long rifle. If it is a carbine, it is either still a legally classified long rifle, or a gun too short for non-LEOs to possess. So, an AR-15 that is legal for sale to non-LEOs is a long rifle regardless. Call it a rifle, a carbine, semi-automatic, even military-style... just please don't call it an "assault rifle" or "assault weapon". "Assualt rifles" are selective-fire carbines that are never legal to publicly carry in the US and are used primarily by the military. "Assault weapon" is a term used almost exclusively in the US and was invented by the anti-gun crowd as a way to strip rights from gun owners.
Ok, tirade over now. Sorry about that, it's just one of those issues that sets me off...