If you look really close at my avitar, you can see that I have both red tail lights on my roll bar and white lights. I plan on making the white lights a switched on and off bed light. I would also like to make them come on when I put my yet to be installed NV4500 in reverse.

Which would be better?

Ground the lights, power to light switch and power to reverse switch on trans, or make the switches the ground and the light have a permanant 12v + supply.

Thanks, I know that this is a simple thing, I am just looking for justification or a nessesity to do it differently than my first option above.