Headlight ground

Quick question. Can I ground the headlight lamp to the shell or maybe the turn signal studs? Reason I ask is I'm working through the previous owners mess and my only prob is where I can run the ground without running 3 grounds into one. 3 being the two turns and the one headlight (which is how he had it...not working lol). Just to be straight, I'm talking about taking the ground from the headlight connector to the headlight shell.
Thanks.

here's the color of the wiring going to the headlight connector:

HEADLIGHT
RED with BLACK stripe, High Beam.
RED with YELLOW stripe, Low Beam.
BLACK with YELLOW stripe, the ground circuit.

Most headlight housings are rubber mounted along with the turn signals & stems. Find a BLACK with YELLOW stripe wire, as it's part of the ground circuit on the bike.

I believe I figured it out. The light was rather dim and I thought it was a ground issue. Rather it was the high beam pin was not attached correctly to the light. Thanks though