Mary Barra tweets photo of Silverado EV testing at the Milford Proving Grounds and a video surfaces of one being spotted on the road. https://twitter.com/i/web/status/1542518964135161859
InsideEVs just published some spy shots as well. I'll drop a couple here, but there's a bunch more at the linked post.
It was taken in Waterford Township, MI. https://www.google.com/maps/@42.692786,-83.3888855,3a,75y,254.42h,95.83t/data=!3m6!1e1!3m4!1s2tpn5dmBC_gZtGPU6SZ_og!2e0!7i16384!8i8192
Dude. I used Google street view to look at every Great Lakes Ace Hardware. The sign is slightly different from streetview, so I wasn't sure this was the right one until I checked them all.
Yeah, but I think you originally misunderstood me. When I said: "I've been trying to find where it came from." I didn't mean location, I meant original poster. Trying to find where it first got posted on the interwebs. xD
ah ha! I should have checked TFL sooner... looks like someone sent them an email and they posted it up on their youtube page.