... if you still have the old fouled plugs, then stick them back in and just see if that makes a difference. It probably was the float adjustment, or maybe you damaged the plug wires in the process, but there's always the slim chance that the "identical plugs" are counterfeit knock-offs. I doubt that's the case, but putting the old ones back in would clear that possibility up. If the problem is still there with the old plugs back in then it was either the float adjustment or you damaged the wires pulling them off.
EDIT -- Educational NGK video on counterfeit spark plugs
http://www.youtube.com/watch?v=b0sB81hI6AI