I take it you have all seen his air cooled mk3???
Yes. How does that cope with the requirement for a cat on that age of vehicle?
Doing radical things to vehicles that are *possible* is relatively easy. Making something that passes an age-correct MOT is another thing.
Cutting the turrets on this car won't cause problems with the DVLA. Notching the
chassis monocoque is starting to intrude into this space, although you would need to talk to someone from the DVLA, read very carefully and probably get it inspected to confirm what impact it has on the car's identity.
The thing that is a big no-no is cutting about the firewall on the car.
Frankly the modifications to this strike me as dysfunctional and pointless, but hey - it's your money. Some people restore double-decker buses for fun: the world is full of weirdos.