I've removed the drop
axle and replaced it with a straight
axle, new springs, new hubs, and bearings.
I measured the position of the springs on the old axle and placed the springs on the new axle in the same spot. I only went up to 14" wheels and kept the wheel wells the same. The net result was a 4 1/2" increase in height.
Check out my two trailers under SouthwestOregon201.