If you have easy access to the nut, then that is a better idea. Not that you probably need the thicker rod, but you may as well go that route as it will only take a minute to drill out the nut. Don't go cheap, use a real good drill bit so your not messing with it forever. And watch your wrist. That bit is going to want to bite those messed up threads and stop, yanking the drill around.I think the easiest thing for me to do is drill the nut out and use a thicker rod with a washer and nut on top. I can easily reach the top of the rod where I need the nut.