leaf springs were great tech in 1850. build a proper 4 link.
I just put an artec 4 link kit into my scrambler with a 5.3.
I ordered the kit for a TJ and installed it with a disk brake 14 bolt
very complete kit but I made the links a little too long and had clearance issues with my (drivers side drop) NP241. I used stock TJ springs and ended up with about 4" of lift. the right way would likely be outboarded coilovers if you want to keep the ride height low, though the AMC 20 width may not allow for it.
Don't forget that you'll likely need new exhaust, brake lines, and fuel line routing because the bracket welds to the frame.