I have a BX2750B snow blower that I ruined one of the augers on. I am trying to pull out the gear box assembly but I can't drive out the hex bolt on the gear box shaft to remove it. It's number 7 on the parts diagram. I tried a punch and then a compressor driver/hammer, and then heating it with a propane torch and driver this all again and it just won't budge. Looking for suggestions. There really isn't room to drill it out.