Fog light wiring help!

[snowphun <pajono@compsol.net>]

Hi all,
  I recently obtained a set of Hella 500 fog lights, not the best, but
none the less good stuff. Anyways, the lights did not come with any
instructions. The lights only have one wire coming out of them, right
off the bulb. How do these things get grounded? I would guess through
the body of the light to the mounting point, but the body is plastic.
  Is this similar to the Hella XL's? I'm planning on adding a set of
Hella driving lights as well and still haven't figured out the
difference between the two.

TIA!
Paul
87 4kcsq getting glasses
86 4kcsq can't see anymore 'cause I pulled out it's eyes (headlights)
=)