Oh ok i've never used illistrator. But all I can say is you need to bust out that ruler and make sure everything is perfectly constant. Test it with a box, then with a box with a stick coming out just to see if your doing it right. Then go to your main object that your trying to model. You see i've done this once before but I drew it by hand making sure everything matched up. It did once I scaned it in and whatnot. Im sorry that I couldn't realy help, and that I don't know of any tutorials.