1st thing to do is take it for an MOT, they can MOT it on the chassis number.
When registering cars that never have in the UK before you take em for an MOT, then take the cert along with some money and loads of paperwork youve filled in down to the DVLA and they give you tax and a registration.
No doubt if its not got VIN plates etc itd be a bit more complex, but it will be the same sort of procedure.
My Chaser is off for its first ever MOT (built 1990) at 2pm today so i can register it for the road... im shitting myself