Fuel pissing out of carby overflow hose.

Oh dear... No, I did not reconnect things in the wrong place. I'll hazard a guess that my spark plug is just not firing at all, so I'll be replacing all 4 today, but if that doesn't fix things, is there anything else it could be? It's only one hose, so one carby, it doesn't SOUND like it's only firing on 3 cylinders, but then again, she sounds like she's dying as a general rule.
1979 Z650, running pods, not airbox. PS does anyone have a spare airbox "lid" (the screw on bit at the top) lying around their garage?
Thank you!
1979 Z650, running pods, not airbox. PS does anyone have a spare airbox "lid" (the screw on bit at the top) lying around their garage?
Thank you!