Leather's directions will work very well. If the plug is available as an orderable item, try taking the whole pumpkin cover off, do leather's thing or try to wedge some pieces of metal in place to hold the hex thing tight. Then use an ELECTRIC impact wrench on it, not a monster air wrench. Now, I did the electric part on mine that was virtually impossible to remove. I didn't have the rounded out problem. It took about 30~45 seconds of impact wrench hammering to break it loose but all was well after it came out. I found being able to rest the pumpkin cover on a pice of cardboard on the ground gave me much better control to avoid any damage. Good Luck.