How do i stop my spotlights vibrating?

Hey everyone... I have a d21 deisel 2x4, as you all probly aware these td27's vibrate a fair bit (probly all deisels)... i am just wondering if anyone has any tips on how to stop ,my spotlights vibrating. They are IPF 100watters (the rectangle ones) and , i have them mounted on my front bar... i am guessing they'd be better on my roof as there seems to be less vibration up there but would rather them be down lower. Anyone got any ideas? Going away for easter and its gonna be a a 4 hour drive in the dark thru some of victoria worst kangaroo areas, kinda wanna fix it before then... cheers riley.

try using a large hose clamp, cut it in half or at an apropriate spot to allow access for ajustment.
Straten the strap out attatch one end to the top of your light and the other to a stable point as close as possible to directly behind your light.
This will brace your light and allow for elivation ajustment.
I hope this is of some help.

or u could mout the spotties on some rubber washers