You would not need anything if it were used on private land or private parks.
To be used in State/Federal/County parks you would only need an ORV sticker.
To be used on ORV trails and routes, you would only need an ORV sticker.
Not sure if the ORV on the shoulder laws apply to a full size vehicle. Might have a problem there without an SOS plate. But I am not sure. Check with your local PD and DNR.