Ford placed one shock ahead of the axle/one behind so that on acceleration/deceleration that they prevent (reduce) axle wrap (pinion moving up when you accelerate, and vice versa).
Explorers went with shock on the front of the housing to prevent wrap as they have both shocks on rear of axle. They also added traction bars when they installed the 5.0 in Explorer. That's the engineering behind it.
It will be harder on your springs as they will now be being twisted in addition to being flexed (I've seen a number of broke leaves on our Rangers as they are getting older and fatigue is failing the metal).
Depending on what you have for springs - heavier ones = less wrap and driving style - unbroken egg on gas pedal = less wrap will determine how adversely it impacts your truck.
If it is too bad you can always install traction (ladder) bars to prevent wrap.