I think the 250 and 350 single use the same main rear spring stack. The difference in 4x4 250 vs 350, would be a 2in vs 4in block. It looks like you have both a 2 and 4 in block, so just run the 4in and you should be fine with stance. Another difference between the 250 and 350, is the 350 gets over loads for added capacity. These are over loads on top of my springs for reference, have yet to put the brackets on the frame for them. Yes this f-super spring stack is massive.
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