Honestly, I'd junk those springs and get something made for a truck or a jeep. If you can weld, or know someone who can, it's a simple task, and the ride is extremely improved over normal trailer springs like you have. My trailer rides as nice, or better than my truck using springs from a Ford Ranger. The hangers can be purchased off a number of different off-road sites ( I think ballistic has them) and they're set up just like you have, but longer, softer leafs. A number of people here use Jeep YJ front leafs I think.
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