As always Les covers this subject very well. I drive an RV which is 102" wide, but the mirrors stick out about 12" on each side, and the awning is 4" and fixed at the top of the RV. It has been explained to me that not only safety, but removable are key words in the size difference between the 102" the legal limit and the actual width. For example my mirrors could be removed, but then the vehicle would be illegal to drive--so it is clear that they must be left in place, but can be folded back if necessary. (these mirror are true side mirrors, not the front mirrors which stick out a little to the side). The "guide on's" for the trailer are a different matter. If necessary they can be removed. So if you were stopped, you could unbolt them, and then put them in the cockpit.
The driver's license is a bit more complicated. Most states (but not all) have exceptions for "recreational" vehicles--which include boat trailers. Some do not and reqire an endorsement or CDL. Some states have "brake" endorsements--especially air brakes.
I remember that the 45 foot length was tested in California--and my recollection was that the RV industry won (there was a 40 foot length restriction).
So if push comes to shove, you have a good chance of 'wining". But I doubt if a recreational boat with 4" extra overhang will be stopped. There are also rules for the Interstate freeways which have to be universal.
But the GVWR is really sticky, since North Carolina defines the GVWR as: "in the absence of the manufacturer's GVWR label
affixed to the vehicle, the registered weight or the actual weight, whichever is greater, shall be the GVWR." Again, it is probably unlikely that you will be stopped (there was a thread on of the boating forum of some Florida boaters being stopped and actually weighed and measured, but this appears to be very rare unless there is some other citation given.
However the North Carolina commercial drivers license web site gives the specific exemption:
"Certain vehicles do not require you to have a CDL in order to drive them. However, you may still need a non-CDL, Class A or B license. These exempt vehicles include:
Recreational vehicles and others used for personal use"
We have been in 47 of the states with RV's or trailers which were slightly over the 102" and never been stopped. This includes the C Dory 25 in about 15 states.