Unfortunately you will find there is just too little metal in the block to play with. The solution isn't that hard but it does require some machining experience. A lathe would be useful but not critical. Simply drill the hole in the block for a head stud and make your own custom nut for it. The total cost in parts is minimal and it will be stronger than the original. You will find the threads in the hole are an off size anyway. Like 6-40? So when you install the new stud you can make the threads any convenient size you want. I think like 6-32 is more common. The nut is made from 1/4" drill rod , drilled and tapped and slotted. Easy really.
I almost forgot. The stud is pinned into the case so it is super strong.