[aerohead]

You could have chosen worse!
Basically speaking, since pickup trucks began from 'passenger cars' ( Ford Model T ), and passenger car-based 'utes' have the lowest drag of all ICE 'pickups,' then, it kind of follows that, your RAM is going to have its lowest drag when it 'looks' the most like a lower drag passenger car.
Taking a look at Stellantis' upcoming electric RAM 1500 'REV' pickup may give you some insight into how FIAT's Dodge Division is handling the streamlining of this pickup in order to make it 'range' competitive with the Silverado, Cybertruck, and Rivian.