My side radiator has a belt-driven fan clutch which attaches to a small drive shaft that spins the radiator fan.
My DEF fill is on the PS, but I must be lucky, because the local station that I fill at most frequently has DEF fill on both sides.
I have had both rear & side radiators. No contest. If you do your own maintenance it's far easier - if you don't, it takes less time and therefore is cheaper.
Bob in West TX
2015 Entegra Cornerstone 45K
2012 Jeep Rubicon, 1994 FXLR