I know a couple that has a 4 1/2" leeway. He hung a couple
sections of conduit down, connected together by another section.
Then he put a microswitch on both of the hanging arms, with an alarm powered
by garage current.
When the bumper pushes it, the driver knows.

I prefer my way better. Tall road cone, when the car pushes it,
it's obvious. I've got 8 feet more space in front, but that's for my
workbench, not a car.

"xrongor" wrote in message
...
they put
the egg on the cone and see how close they could park without hitting it.

randy