Ed - I really don't know what rules I was judged against.
But I've just gone back to check the Gov.UK rules on Rebuilds.
Keep a vehicle’s original registration number
A rebuilt vehicle can keep its original registration number if you can prove you’ve used:
- the original unmodified chassis or bodyshell (car or light van)
- a new chassis or monocoque bodyshell of the same specification as the original (car or light van)
You must also have 2 other major components from the original vehicle from the following lists.
For cars or light vans:
- suspension (front and back)
- steering assembly
- axles (both)
- transmission
- engine
The key to the Sammio, Ribble & Miglia builds is keeping an unmodified chassis to ensure no IVA requirement.
You can still do some things to the chassis and keep within the DVLA definition of "unmodified".