Rmerritt

GMC Sierra 1500 4x4 2012. Went to a mechanic to scan why my airbag sensor light was on. He said my passenger side sensor was bad. Can someone tell me how in the !@#$ im I suppose to get to this screw which is located on the opposite side? It has a bout a half an inch of room. I know you need to disconnect the battery and so on... just dont know how i can get this off or even back on. Is there some trick or special tool? Ive included a couple of pics for reference. The top of the screw is where I circled. Any help would be MUCH appreciated.