Bolt / nut problems

I'm trying to add a bracket for an axillary light, but the circled bolt won't come loose from the nut inside. The nut spins. I can grind the top of the bolt off, but I'm curious about the nut on the inside. How to replace it.
I'm going to guess that the windshield has never been folded down and I've only tried these 2 bolts so far.
Thanks everyone!

Yeah, I agree it is stuck. I can rotate the bolt and "feel" the nut rotating. Grinding off the bolt head is not a problem. but replacing the nut is where my concerns are. I have a nutsert tool and several different metric size nutserts. As this is my first time at removing these bolts, I have no idea what to expect on the other side of this bracket. I know it messed the paint up when they busted loose. (not a worry) The other bolt came out without a problem. Once the windshield is folded down, can you access these nuts? I'm up for almost anything except welding. I have a star bit that fits these bolts. Maybe weld something to the nut, if there is access.
Give me my CJ2A or CJ5, I know about those.

After watching this video, I've decided my pod-lights will have to wait until next summer as winter is not too far away here in north Idaho. As much as I would like to have them my headlights and fog lights will have to do.

I watched 2 different YT videos that address the problem I'm having with my windshield bolts. The problem is the captive square nut inside the windshield frame gets rusted onto the bolt and spins with the bolt when you try to remove it.

In one video, the owner welded a t-nut onto the inside of the windshield frame without aligning the t-nuts with the bracket. One side didn't fit.

In the second video, the owner used a nutsert tool to replace the rusty nut. That video ended before we got to see how well the nutsert was aligned with the bracket.

My thoughts: I'm going to make a new nut by cutting a piece of steel to fit in where the square nut was at, but make it a rectangle (one inch long or so) instead of a square. I can drill a hole and tap it and replace the nut on the inside. Bad part is I have to fold the windshield down in order to get it in place. A little bit of anti-seize when I put the bolt in and it will be all set.