Lucky,
See if your state has a paper tag for temporary use. For example, in Texas, I got a 30 day temp tag for $25 (actually many times). Beats a rush job on a trailer, and takes the pressure off the INSPECTION/registration process. Used the frame number, insurance, and no inspection required. Most states also have a "trip tag" for unregistered vehicles, but you would fudge a bit, since you're not going anywhere one way, but it may give you something to laminate and hang on the car going to inspection, etc.