Dont forget to check for air leak at the choke shaft too. And the main Butterfly. KRS is right. All you are doing is substituting the unplanned air (vacuum) leak for what the choke plate would be doing.
I found my problem. The coil was putting out a very weak spark. Replaced the coil, have a sharp blue spark and the thing starts right up in a second or two. Don't even have to choke it now in the hot weather.
Glad you found the problem. It must have been hard trying to drive it with one hand over the back of the carb. Kind of like those motorcycle riders on a curve where their knee is almost touching the ground. A real Kentucky lean.