Trying to install Cooper surface LED down light to ceiling but don't see a ground wire

Question

I'm trying to install a Cooper LED down light to a pre-existing ceiling metal electric box that has been un-used.

I know to turn off electricity at the breaker and that white wire from light fixture goes with white wire from electric box and black wire from the light fixture goes to the black wire from electric box.

The mounting strip of the fixture has a ground wire coming from it. But I don't see a ground wire coming from the metal electric box. So I'm not sure where it goes. Do I need to get a green grounding screw and screw it into one of the holes I see in the top of the electric box?

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I also have other ones of these LED down lights that were installed. I'm not sure how to take them down to look at them as models for what i"m supposed to do. Does anyone have any tips on taking down these Cooper LED Ceiling Surface LED lights? I'm trying to turn them clockwise (and counter clockwise) to release them from the j-box bracket but not getting a good grip to turn it. Any tips here will be helpful

Answer 1

If you look inside the box, there is a raised hump with a tapped hole for a ground screw.

Since it looks like your ceiling box is wired with armored cable, the box has no ground conductor as the armor around the cable is the ground conductor. The screw size is 10-32 and you can find packs of green grounding screws at home improvement centers.