Fairly easy to clone a Mog? Well I know of a situation where a high value Mog was sold overseas and when the new owner went to register it with the vehicle registration department, he was told his car couldn't be registered as that chassis number was already in use.
Also, there's at least one Plus 4 Super Sports in existence with a suffix after its chassis number due to the chassis number being in use.
Also, there was a certain character in the Morgan Three Wheeler Club who was into building specials. A built a few, all with the same chassis number and sold them abroad, keeping the chassis number/V5 for his UK car - God knows what's going to happen when someone decides to re import one!
Arwyn