Actually, I think they changed the rules.
When I built my first kit, there was a points system: so many for the engine, the gear box, wheels, front and rear suspension, interior parts and so on. So people would buy a dead car with useful bits, register changes of engine on that, and then transfer into the kit, and keep an age-related plate.
I ended up with a Q plate, it was a bit of a Heinz
- Front suspension - Ford Cortina
- Rear suspension - Ford Escort
- Engine & box - Datsun 140Y
- Radiator - Morris Marina
- Steering, pedal box, and instruments - Datsun 240Z
- Fuel tank - Datsun Bluebird
- Seats - Triumph Spitfire
- Filler cap - London bus
The bodywork was aluminium covered marine ply; the chassis was welded steel tubing.