I sent a car to Kauai about 23 years ago. They told me at the Long Beach port to make sure I removed anything loose from inside the car and to not include any personal items. When I picked up the car in Kauai, the glove compartment was opened and the contents, which I had not removed, were strewn all over the floor. There were some items missing. The tire inflator, which I had stored with the spare tire was still there, however. I would recommend taking their advice and not leaving anything loose in the car and shipping it separately. Items such as the UMC come to mind.
They let me drive with my AZ plates until they expired, but I had to have a safety inspection done and have one of those nasty stickers on my bumper. Having the safety inspection period not coincide with the registration period became a nuisance later on since you have to have a safety inspection before being able to register you vehicle, which made the out of sync inspection and registration a hassle.