I was just reminded of an event from my mis-spent youth.
When I was in my early 20s, I was part of the English Civil War Society, who travelled all over England (and occasionally Scotland) reenacting the battles of the English Civil War.
My regiment acquired an ancient 7.5T British Leyland Redline truck, ex-British Rail, which was perfect for our needs; It had seating in the back for a dozen people (in comfort, with tables and everything), plus a big cargo area behind for all our gear - Tents, muskets, etc; It even had a boxed in section the length of the vehicle which could be used to carry pikes and polearms, and a segregated flammables box we could carry black powder in. But best of all, it was CHEAP. This was due to it being about thirty years old, and having been thrashed to death over every last one of the miles before and after the odometer rolled over.
So, as we expected, bits occasionally fell off, and needed to be replaced; But that was OK, because one of our members was an auto mechanic. So he got it through its MOT (roadworthiness test), and we got it registered and good to go.
Unknown to us (or the MOT test station), the alternator was on its last legs. And a few weeks after passing its MOT, it gave up the ghost, and stopped charging the battery. We were on a long trip from an event in the South West, back to our base in Yorkshire; and as night fell, Dave, our driver, turned on the headlights. But despite the headlight switch being in the 'on' position, no light came from the headlights. Indeed, all of the electrics had ceased to work - but being an old Leyland diesel, with no electric components other than the starter motor, the engine kept on going, and we were none the wiser.
So in deepening gloom, our light-less truck climbed slowly up the M62, with Dave managing to get no better than 50mph out of it with his foot flat to the floor. All of a sudden, blue flashing lights appear in the rear view mirror. Dave eases the truck over onto the hard shoulder, and waits. The cop climbs out of his patrol car, adjusts his cap, and walks up to the cab. He shines his torch in through the driver's window, to see Dave, wearing the uniform of a 17th Century infantry officer, complete with feather in his hat. Dave slowly winds down the window, and the cop looks him up and down, slowly, three times. And finally he says, "I've come as a policeman. What have you come as"?