There is no gain power or fuel economy wise by replacing a properly functioning clutch driven radiator fan with an electric fan unless you do a lot of idling. Then and only then will you get better idling efficiency, but its still only 5-10%.
A properly functioning fan clutch will spin the fan decently fast at idle and under light accel at low speeds depending on the water pump temp. Under heavy load it will spin up for a second or two before freewheeling and settling at a speed similar to a high idle.
If the clutch is malfunctioning and is stuck on, then yes switching to an electric fan will make a significant improvement in how the truck feels accelerating and cruising, but so will just replacing the clutch.
The only things you should consider switching to an electric fan is as follows. You want more room in the front of the engine, or like the look of not having a fan coming from the engine. Need improved low speed low RPM or idle cooling, have a huge trans cooler and A/C performance is suffering, or you want a slightly quieter engine when accelerating.
Installing one is easy enough, i'd recommend getting either a dual fan variant or a large two speed fan. That way the smaller one/low speed mode will run most of the time and use a little bit of power while also being quiet. Then when it keeps heating up the large fan or high speed mode will kick in and cool that baby down.