Right after delivery of my first new car I drove gently for the first two days. Suddenly after 250 miles on the car I heard an unusual rattle from the engine. Immediately shut it off and coasted into a nearby driveway. Called the dealership which, a day later, sent a tilt back truck to pick it up.

Upon disassembly it was determined a valve had broken and was bouncing up and down in the cylinder. The story I got was the cylinder walls were not damaged but the cylinder head was. (In hindsight I wonder about the top of the piston and how lucky or impossible it was for the cylinder walls not to be scored.) Dealership said it would take 30 days to get a new cylinder head from England. I hit the roof. Only had the car two days and didn't want to be without it for 30 plus. So I told them to take a cylinder head off one of the many new E-Types on their lot and put it on my car.

That's what they did under warranty. So even today there could be those two 1970 E-Types with the wrong cylinder heads on them. Some restorer may be lamenting the non-numbers matching engines.

BTW, had an entire engine replaced under warranty on my 3 year old, 34,000 mile 2000 Corvette. No numbers matching there either.