Yes, double clutch going down. You need to clutch, take out of gear, rev. engine to match higher rpm of lower gear, clutch and put in gear. Not sure about the 2 speed rear ends, if you have one.
It's all about matching the engine speed. So listen carefully at the shift points as well as watching the speed at those points. It's also possible to shift without using the clutch. That's when you really know your truck. You are almost there!