I think I have the same trailer it sets fairly high which is one of the reasons I bought it because it gives me enough clearance for the bed.
Does your axle set below the spring's or above? Mine sets above the axle and seems high but tows just fine with my 4x4 f250.
It has square tubeing above the hangers that may have been added? If it had flip axles it would be really high.
Dose yours set level with the truck? I think that what your looking for.
If you want any pictures let me know ?
Never. Mind I just realized that you want to move the axels further back? Wow that that would be a lot of work! (I thought you wanted to go back to stock) mine would have way to much pin weight!