[Espeefan]

What I would do is ditch the stock leaf spring pack, and build a new one. Or replace it with a solid piece of bar stock to act as an equalizing bar. 4 link the axles in place, and then you can make the links longer to get the spread you need between the axles, in order to run larger tires. If you're not sure what 4 link suspensions are, check out some rock crawlers on the internet.