boost gauge questions

[BlackVert]

i bought an auto-meter "sport-comp" 2 1/16" boost gauge a while ago from jr. since it was used, there are no instructions. 2 wires on the back, white and black.

do i just hook them up to a 12v source (black=pos, white=neg) that becomes available when the key is turned?

i can handle hooking the vac/boost line to the blower.

 

[95cobraguy]

those 2 wires are for the light source at night, so the black is a ground and the white u tap into the headlight or parking lights. i run those light source wires to the under dash fuse box and find the fuse that powers up when the headlights are turned on.