I hired a Morgan 4/4 for a long weekend in the summer of 1976. An orange one.
We, the then current love of my life, and I set off for a British Grand Prix practice day at Brands. Driving along the Embankment in London this jealous fellow in a maroon Ford Anglia 105E kept blowing his horn at me - until we pulled up at a set of lights and he informed me that effectively my indicators had been wired up in reverse. We drove over Battersea Bridge, stopped and Lo! He was right.
So for three days I drove indicating left when I was turning right and vice versa. On the fourth day the indicator stalk gave way and fell out of its mounting to be saved from total dislocation by its wiring and it was back to hand signals!
We also had an oil leak. At 70 mph great streaks of oil appeared along the bonnet, emanating from the louvres, and splattered across the windscreen. It transpired that the rocker box gasket had been twisted and oil was escaping!