Alright, spoke too soon I guess. That hole wasn't spewing gas because the injector wasn't firing. The first time I put it back together one of the pins didn't line up properly. The plug itself is just a couple of pins free floating - no molded plastic to keep them centered. After assembling it a second time it started spewing gas out the barrel that had the original problem. This is after swapping the injectors front to back. Has to be electrical, but I couldn't find anything glaringly wrong with it. Back to Holley it goes. Already have a return label. Thank you everyone for your help.