Apart from dealing with DVLA? As to first registration, yes, that happned to me bringing my WC54 Katy back from Jersey onto her old English number. If the vehicle had a previous civillian plate and you have a record, try asking for it. I did and SSY823 was still available so she got it back. The MOT will be nessacary for first registration and issue of a tax disc regardless of age I have been told.