I added a SiriusXM receiver to mine. Duckogram is right about the antenna being the hard part. I put mine on the dash by the VIN and it worked great when I was going South, but not great going in other directions. Following some advice I found in old threads here, I moved it under the mattress of the bunk above the cab. That works better, but reception still isn't ideal. I'm debating drilling a hole in the roof and getting the antenna up there. Haven't decided if I want to do that.
Connecting the receiver to the stereo is simple. Remove the stereo, plug in the receiver, connect the antenna, cram everything back in the dash, and you're done.
2013 Sunseeker 3170DS