Bolts for Body Bushings

I am in the process of changing out the body bushings on my recently obtained 1988 wrangler. I am looking for some assistance on the front bushings (closest to the front tires), are they held in place by a nut or do the screw into the body?
The problem I have is that on the right side the lower bushings in gone and the bolt is just hanging in place, it turns but it should just fall out....
Any help would be great.....

Don't know for sure, but if the bolt is turning, I'd think that the nut has corroded onto it and fused. You may have to use alternate methods, like coca cola or a rotary saw, to remove it.