The final step - getting the car registered with the DVLA and a registration number allocated to Tigger, requires the submission of a fair amount of documentation:
Proof of identity
Proof of address
Certificate of New (provided by Caterham)
Certificate of Insurance
IVA test certificate
Invoices for parts used in the build (supplied by Caterham)
DVLA form v55 (application for first vehicle registration)
DVLA form v627 (built up vehicle report)
Self-addressed stamped envelope
Payment for registration process and road tax.
The above is all required to be submitted in hardcopy form (posted to DVLA) and they set expectations of a 4 week turn around to respond with the V5C logbook (registration) document - which finally makes the car road legal.
In the event, mine took 6 weeks and required multiple phone calls to find out (after 4 weeks) that the application had been routed to the incorrect department.
FINALLY ON THE ROAD!!