help with aftermarket headunit install
 

can someone please help me figure out how to hook up the headunit to the car. i bought the metra wiring harness but dont know where to ground the black wire from my headunit. on the stock heaunit i know there is like a little metal attachment that may be for grounding. by the way its a 2000 x5. any help as soon as possible would be greatly appreciated.

Are you looking for the ground coming off the new head unit or the ground in the metra harness?

there is a spade connection coming off the headunit which needs to be grounded but i cant find a location to ground it.