Now that everything was connected, I was finally ready to try cycling some cylinders and see how this thing worked!!!
I fired up the truck, engaged the PTO, and then carefully started moving some levers. First I figured out which ones were for the outriggers, and cycled them down so that it would be nice and stable. As they started to apply pressure, the second tank started to foam hydraulic fluid out the filler neck cap! I figured it was a bit of air getting purged out of the system, so no big deal, I just put a pan under after I already had a mess!
Then I started actuating the other valves to unfold the crane. It moved really slow, which I attributed to the air in the system.