My bolt does move but it pushes the outer wall of the leaf spring out because its moving with the inner sleeve

my idea was just to back it out far enough and then cut the bolt

 

Ya back it out far enough to get the threads out of the nut and then cut it .

 

I used a claw hammer to pull outward on the head of the bolt while I used my impact to spin the bolt until the rust wore off and the bolt came out. You want to make sure it's not sitting on the nut before you do this, otherwise you might mess up the lead-in thread.

 

Your very lucky the bolt is moving. Be grateful lol. Because you can now use MAP gas and torch tip to essentially burn the bolt and sleeve cherry red. Cool it down and then cherry red again. After a few cycles of this you'll be able to get it to loosen up. If not a Sawzall with sharp blade will finish but make sure it's got some stub hanging out so you can get the part of the captured nut in frame.

 

i heated up the nut through the back through frame and both started turning pretty easily, no amount of heating the head would get it to move