The department of transportation/motor vehicles should be able to answer any of your questions. wherever you would go to register your vehicle should have all necessary paper work for a reconstructed/altered vehicle<if needed> and a basic ideas of the steps needed. ie State police/ or inspection mechanic saying it is ok for the street, 3 pictures to send off to DOT etc etc. A motorcycle inspection station<if applicable> or the state police should be able to tell you the recquirements of the vehicle to be street legal in your state.
Pennsylvania recquires
Vehicles manufactured after 1973 need turn signals and a rear running lamp,after 1978 charging/battery system so that headlights,brake lights and turn signal wont dim when engine is running and the tail light lit when engine not running.
all vehicles need a Hi/low beam headlight and a high beam indicator,brake lights and liscence plate light. All recquired lighting DOT approved. there is specifics about how much candlepower,mounting,and visibility that would be too much too type.
Horn, DOT tires, mirrors, spedometer, non resetable odometer on vehicles less than 25 years old. Exhaust systems not modified to make it louder and shielded so you can't burn yourself. Two stroke owners need to wrap their pipes to comply. There is rake and trail recquirements of not less then 20 degrees and 2 " positive<KTM owners beware when looking at those fancy triple clamps>. Plus the standard inspection of making sure the vehicle is in good operating condition,tires bald, brakes worn, forks leaking etc etc.
In Pennsylvania If you can get a State Trooper to inspect and sign off the Reconstructed/Altered vehicle title form saying it passes you have a better chance of it going thru DOT for a street legal title.