Car Body Modifications

I'm considering shortening a few cars, and stretching a few too (limo's) and I haven't had much luck in finding out what it takes to actually make it street legal. If you are wondering the type of stuff I'm considering doing, a good example is the video at the URL: http://www.youtube.com/watchv=VLHCpa_kNeE

If any of you are familiar with the Buick Shortmaster of Davidsfarm, that is the basic idea. However, I just need to know what I need to do to keep the vehicle street legal. (Other than emissions, turn signals, 5 mph bumpers etc....) Any help or links you can offer would be great. Thanks for you time, expertise, and for looking.
-Beetleman

It depends on the state. In your case, I would look at the Utah vehicle code.