Are you implying that the UK administration is corrupt and bribery is common place?very few SFC 750's were officially sold and imported to the UK, might have been six, but one of them (that I know of) was sold new to Bob Hall who used it on the road. It had a fibreglass tank. Jota's and Monty's were sold in the hundreds for road use and the exhaust system was NEVER quiet enough to meet the required standards, but still sold and still registered, it says more about the UK registration system than anything else.
Plenty of cars these days, both petrol and diesel, have plastic tanks, it was the Americans who thought it a good idea to mount the tank between the axles rather than hanging out just under the rear bumper. Electric cars have their batteries housed in plastic, and have you seen how they can burn in a relatively slow speed collision that causes an electric short?