Cleaning out one of my storage areas and have a standard bore '57 312 block that I managed to strip out the last 1/2 inch of threads for one of the main bearings. Did this many years ago in my mispent youth. Used a longer bolt and some washers and put it back togeather. Ran it till the rings went south. Question is can it be repaired properly with a heilicoil and hold up? Hate to scrap it if it could be repaired. It would also need a rebore if I ever had to use it. I have a couple of 292 blocks I could use if I ever need on. Should I save it or scrap it?