Here are a few pictures of the ROPS mount, and how I built a bracket that used the existing bolts that go into a cast corner bracket between the top bar and side posts of the factory ROPS. If I had it to do over, I would only slot one hole, not both. In a hard rollover, the brackets could slide out from under the bolt heads. The whole cage is designed to slide to the rear 3-4" for removal.
The lower mounts to the loader brackets just clam-shell around the 3" box tube they are made of... simple enough in design.