I'm pretty sure that it is supposed to be red. There's a lightbulb (1 or 2 candlepower) that goes into the dash (I think) that lights up a translucent red dot, which indicates the high beams.
The only 51 that I have access to is currently indisposed in the woods under 3 feet of snow, so I can't verify that, but I'm pretty sure that it was red.
