im in texas - probably best to call Texas DPS (department of public safety) -
no matter what happens youll need a weigh slip to prove the weight of the coach...which is how they determine how much your annual tags will be.
theres no one verifying the accuracy of your weight or weigh slip...so you COULD hang a couple of wheels off the scales, lowering the weight and there for your annual tag fee.
the truck stop (cat scales) will give you your weigh slip (its up to the driver to make sure he's weighted the truck properly...or not)...youll have to show that weigh slip to the DPS (county tax assessor when you register your truck/coach).