Did you fill in the V55/5 form to register the bike ? Is so you should have put its taxation class as "Historic". Chris Brooks on here is the MVT man you need to speak to regarding anything registration related he can help I'm sure. It should be straightforward if the paperwork is all in order. You need valid insurance done on its frame number and your dating certificate, a completed V55/5 (available from DVLA), and proof of identification etc. The V55/5 tells you all you need. I found if you obey the guidelines to the letter DVLA are usually fine. Good Luck.