another quick wirring question

[SilverLS]

Im installing a voltage gauge and a a/f gauge im trying to do this the easy way is there a switched power when the car comes on in the headlight switch or in the immd area i dont wanna tap into a thick gauge wire becuz the taps i have arent that big so if i can get some help?? also the black wire in the headlight switch is aground right i cant find my test light so ???
thanks again in advanced

 

[Quik LS]

I grounded the black wires to a screw used to hold the dash to the firewall - it's in the access panel at the end of the dash when you open the door.

I tapped the guage lights to the dash guage dimmer switch - so their brightness follows the dash.

For switched 12v - there is a spot under the dash - somewhere - I'll look when I get home and post it for you.

 

[SilverLS]

thanks for the info im just gonna tap into the radio's swithced pwr...