What it sounds like you are looking to do is generally called "flipping the axle" which is done with an over/under kit. There are two options available for you depending on your axle's diameter. For a round 2-3/8" axle you will need the Dexter Trailer Springs Over-Under Conversion Kit # K71-384-00 while for a round 3" axle you need the Dexter Trailer Springs Over-Under Conversion Kit # K71-385-00. If you had tandem axles you would need one kit per axle.
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