I got my 2 car insurance with Admiral before they did the multicar thing and they just replicated my NCD from one car to the other.

They also advised me to put the 2nd car in my wifes name to reduce my premium, and then copied the NCD to her too
_________________________
Mk2a RioCar 120Gb - now sold to the owner of my old car
Rio Karma - now on ebay...