ya know, ill bet you could actually make it street legal. i mean there are tons of vehicles that dont have a crash test rating, or any of those other things. you would have to do ALOT of modifications, but i would look into registering it as a bike, or in a smilar class. i mean if anyone here has heard of the T-rex...its like a two seater 3 wheel bike. but it has like a steering wheel, side by side seats...anyways they can be registered here...why not a golf cart..
now as far as the fabrications go, you obviously would need to reinforce everything, i mean this is just a rough estimate...but to actually do this you would probably be spending somewere around 20,000 dollars....and thats just not worth it...so instead of thinking about whether or not it can be registered, you should be thinking about what fabrication needs to be done to make it legal to be registered.....