72 Scamp Rear Leave Spring bracket removal help / suggestions?

And they are fairly easy to twist off. Heat usually helps. Sometimes you have to drill access holes, well above the bolts, and flood the area with a penetrating fluid, then wait a few hours and try again. Work the bolts back and forth until they loosen up, but easy does it, they are not very strong. If you bust them, don't panic. They can be removed; it just takes sooooooooooo much longer;
heat is your friend. Crank up the torch, and Heat the bolt heads up cherry-red, fast, so as not to affect the nuts ; then walk away. When they cool they will shrink away from the nuts. A lil more lube and they will practically unscrew themselves. Then throw those bolts away. Anti-seize the new ones.