It’s going require grinding that nut off if you round it off, of course, you’re wearing the appropriate PPE if you do start grinding anything.
If it’s been compromised and you have to grind it, of course, what did I say, just replace it. The bolts, if you stripped them, replace them.
So, everything on this particular valve is in good repair at all times.
So, if you follow those procedures, you’ll get the longevity required from an item such as that. Trouble-free motoring.