The maximum legal height for bumpers is 25 inches from the bottom of the bumper to the ground. If you attach something to the bumper to make it conform to the legal height, it must be just as strong as the factory bumper or meet SAE standards. Simply bolting on pieces of wood or metal isn't gonna cut it folks. If you slap on a lift kit, you might actually be required to register your truck as a "reconstructed" vehicle, and that would mean you'll have to pay additional road-use tax and need an inspection where a new VIN would be applied.
I think this depends on where the vehicle will be driven mostly. I used to drive my 78 down in the cities and was HARASSED by the police constantly. I moved away from that communist enviroment were nobody cares about how big your truck is because you have to worry more about things like combines driving down the road. I recently lifted our 82 bronco 2 1/2 inches and it rides on 33's. I have a 78 F-150 with 4 inches of lift. I have never been told or have heard anything about registering them as reconstructed vehicles. All I know is that Minnesota is a bumper height state. Some states are bumper some are headlight height states and a couple of states just dont care. And as far as tires sticking out. They are not supposed to. By law you should have fender flares to cover the tires. I think this applies in all states.