Getting it mounted was the hardest part of the job by far - definitely for two people. This thing is heavy and a bit unwieldy.
Everything else, though, I managed to do myself with little more than a pair of screwdrivers. The wiring is dead simple, the manual is detailed, and Outback's support team and community are extremely helpful. A nice prewired GSLC load center comes with all the cables needed to attach to the Radian, and will seal the bottom of the system against rodential intrusion. It's very important to read everything in the manual and make as much preparation as possible before beginning, so you know exactly what wires to connect and what settings to use during install. As the Radian has no interface mechanism, a MATE3 is required (MATE3s recommended for the newest firmware versions and Grid usage, but the Radian I received was on an old-enough firmware version that a legacy MATE3 works perfectly with it in an Off-Grid setup) to set any specific configuration features. There are about a dozen different modes of operation to choose from, most of which are focused on Grid-Interactive setups or systems where a generator runs nearly constantly - consistent AC setups. If your primary power source is DC, it's likely you'll just use Generator mode and ignore all the other options.
The system accepts 50A AC, but only supplies 33A, so keep that in mind if you're going to be doing a pass-through from a large generator to a heavy load, a 12kW input will only provide an 8kW…
