hella 500 lights help

i just bought some hella 500 lights. my question is the lights has two wires coming out. black and gray. the instruction doesnt say anything about the two wires. so where do the black wire and gray wire connect too?

 

black can be ground, and grey can be power.

 

black is ground...blue/gray wire is hot.

 

so i can connect the gray wire to positive battery

 

yeap,gray positive

 

I'd recommend a switch first

 

yes....but i would install a fusible link between them.

 

lol id say switch mod sounds better