Steering box bolt failure

What happens some times with these bolts is that they loosen up over time. And probably without your knowledge , the steering got slightly looser. Meanwhile the bolts waller around in the threads and wear them out. It is good practice to check them regularly. When I restore a car, I always use red thread locker on them to prevent loosening. You can probably use a helicoil or a keensert to fix the threads.