Hydro, I run two housings from each HLG1050 MW driver...each housing is grounded then joined together at the driver ground on the AC side and everybody is then attached to the house ground at the plug. GFCI plug and an AFCI plug isn't a bad idea either....
This follows code in my area...also technically you don't need to do a ground at all...seen a two prong plug? It was never grounded....and worked fine, just that if something did go wrong, you made sure you weren't in the path....There are lots of variations on the grounding theme, not just "one" way. Not even one "right" way either....
Also if you search a little farther back in time say 24 months, a lot of the DIY stuff was more in depth due to the newness and people helping out...now alot of those threads just died off over the last 6 months and never refreshed and nobody goes back far enough in their searches or something....
@SSGrower
have you ran across the Solid State Relay / Resettable Thermostatic Fan Switch for your operating needs?
I posted the diagram many times, I will see if I can dig it out again, really just a 12v solid state relay 15A [$4 on Ebay] ran in a loop with a thermostatic fan switch and your 12v fans....
Mine switches were set at 75C....and attached to the Heatsink in the hottest location I could find.....basically if the Fans cut out, the solid state relay will kill the driver....if the Heat rises above 75C it will turn off the Resettable ThermoSwitch and shut down the fans...You will need to reset the button manually in this example, but better than turning back on.....