Case bolts { Like valve cover bolts on a car 7/16 or smaller ..I always was taught 30 yrs ago, t] to use a 1/4 in drive , because your not aware of the extra torqe put on the bolt due to the extra weight of the rachet and leveage] and use only your thumb and first 2 fingers when torqeing,,not only does it keep you from breaking bolts,but over smashing the gasket causeing leaks,,,Lord knows,,I did quite a few yrs ago,,,, either way,,,with that being said,,,,You can either [ A] smear permatex into the hole,flush with the case, and monitor it,,going from hot to cold when the metal will exspand and contract,,,if no leaks,,,there you go,,watch it everytime you start it up and when you shut it down.
Tear it down and fix it right,,it painstakeing andtime consuming,,but get an easyout and or their is a reverse drill hog device..I forget the name of it,,but you get like 2 different size bits in a kit,,,I thought that even walmart had them,,but I know the part stores do,,it looks simular to a easyout but its tapered and quick to pull the bolt out with reverse threads,,,their nice, and cheap,and they grab the bolt in one step,,,,,,I dont know how prestine your bike is,or what all you did to the motor,,but if its a show bike,then its a no brainer,,plan B,,butI dont think its going to leak,,but youll always know its there,,,try the former first,,,,best wishes,,,,I think we all have done this somehere along the lines,,so we feel your pain,,,,,,
