Wiring work lights

[killdozerd11]

That has been done before with magnets and it will work ...BTDT

use strong magnets

But use two wires both hot and ground as they do not ground unless they scratch thru the paint

and they will fall off with rapid stops and reverses sometimes if the magnets are not strong enough

 

[DELInstallations]

As the electrician in me would say, I would run a separate ground irregardless, wherever possible and practical. Automotive is one thing, but I'd say avoid the potential issues.