Put the C-band dish right BEHIND that one at around 8 feet away, and on a pole tall enough where the bottom edge of the C-band dish never gets lower than about 5 ft from the ground, or a height where you won't clock your head running under it with a rider lawnmower.
The KU dish sees much higher than what it looks like it's looking at, and the C-band dish being behind, and higher, won't interfere or be interfered with the ku dish.
180~ft run is fine, and well within specs, IF, you use a GOOD Rg-6 full copper (not copper over steel) coax. I am VERY partial to quad-shield coax, and I don't buy the cheap stuff. I get it on a 1,000ft reel. I go through those about every two or so years with reconfigs and such. Run some spare/extra coaxs out there at the same time. It's easier at the beginning with your trench, than later if you have a bad coax, or want another run for something else. I put mine in polyethylene coiled pipe. Saves my coax from a wife with a shovel, when she's working on the yard...
Add some Thomas-Betts quad shield coax compression connectors, and a kit to install them. You'll likely need some 12 gauge wiring to run out that far for motor wiring, and some 2 conductor 16 (or even 18) gauge SHIELDED wire for the motor sensor. IF you plan on having old-school lnb with a servo setup, add another separate shielded cable with 4 conductors for that.