YES.....
AT 61" to truck bed rail you will need to lift the 5th wheel in order to:
*Tow level
*Have at min 6" bedrail clearance
That would require:
*Axle Flip.....moving leak springs to top of axles IF not already on top
*A 3"--4" 'sub-frame' (cut spring shackles OFF, weld boxed tubing in needed height 3",4" 6" etc to obtain level tow/bedrail clearance), weld shackles back on and add cross tubing for lateral support
Or go back stock on truck and maybe have clearance/towing level with just adjustments to pin box/hitch
There you go.