First thing you need to get is Safety. And they are going to need your car for it... plus that Hawaii insurance card/registration/shipping bill of lading to pass.
If you have aftermarket suspension, or something crazy; you're going to need recon. which is a bitch... hopefully you don't need it.
after you get that, then you bring everything to the DMV (satellite city hall is what they call it) with your safety slip and all the other forms to get it registered. If you're in the military, you're going to need that "non-residency" form so your registration jumps down to 20 something bucks vice 200 something. But only if you want hawaii plates... if you go out of state, it'll cost you the norm 200 something.
Loop hole: The shipping company gives you a bill of lading good for 30 days or so for registration. So you technically can be out of safety spec and run your out of state plates until those 30 days are up. so if your car needs recon, you make an appointment (which is usually booked for a month) and show up for the inspection. if you fail, they give you a notice for such and such days for you to fix it. Basically extending your out of state, no safety requirements until you get recon. Pretty crazy, eh? So technically you can keep going forever as long as you keep showing up at the recon place and getting extensions.
The only reason why i didn't do this in the first place was because my base stickers expired. in order to get new base stickers, you need up to date safety and registration. so yeah... I'm sure you don't have to do all that
