Interesting rig, looks like it would take a bit of experimentation to get good with it. Any movement on the first gannon would change the angles on the second gannon which also has it own adjustment
Yeah, depends on how precise I want the result to be. Generally both are only used together for ripping and rough grading.
Basically I set the side angle to what it should be with the hydraulic side link, then adjust the first one with the 3-point and hydraulic top link. That leaves the second one at whatever height/angle it is, since only the axle height is adjustable.
If being picky, I could use a low, straight, or raised, pintle hook mount, but it's easier to use a 5-foot extension between the pintle and second box blade, making it less sensitive to the height of the pintle hook. That also helps a lot when pulling only the little one by itself.
Also, the second one can't really be lowered and used until the first one has established the correct side angle, since what the second blade cuts is the angle it'll keep creating, with the tires blindly following its own cut.
All this would be much simpler if the ground here was flat, but because of the irrigation ditches it is not. Fighting mounds (mini ridges, really) built up over decades by prairie dogs is what most of my grading is all about. It's a bit of work, but easier than trying to make water flow uphill.