Just read this link in MCN today about searching out your old FSIE (or first bike etc).
  Sadly I dont know the reg. of my beloved (

) first Fizzy but have seen that some of my old bikes are alive and kicking! 
 Only basic info on machine type / number of owners and last change etc - no details on existing owner, for obvious reasons. 
 You need to register with the RAC as well - but its painless..  
https://www.rac.co.uk/myrac/vehicle_data_check/  I might just dig out a picture of my dear yeelllooow Fizzy ! 
 Frank