Cut them off with a grinder. I would bet there is a rusty hole behind that mount as well, as that chassis is not great 🤔

They should be nuts & bolts. They are not captured Grind the heads that you can see off & push the remains out the rear

Thanks, I figured out the issue. The bolts are long and go all the way through to the other side of the frame. I might still have to cut them off. Finale: cut off the bolt heads with 4in angle cutting disc and they punched through easily...

While replacing second rear shock the post at the top of the shock mount broke when attempting to remove the nut. To replace the mount requires removal and it is is held to the frame with three bolts with 17mm heads. These are turning in the...

In the second picture there looks like there is some corrosion on the gasket around the water port which could be enough for it to seep out.