skipnchar wrote:
Usual time to remove nylon plug with screw driver or chisel is about 15 minutes. Drill a hole in the middle then use tool of choice too cave it into the center hole.
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The problem with that Skip is that the middle was already hollowed out if that makes sense. The plug was only solid on the very end, the part of the threads that screw into the tank is hollow and you only have just enough where the treads screws in if that helps. You probably have an 1/8th to 3/16th of threads there the rest is hollowed out.