Finally got everything installed. I pondered a lot of options, but decided to buy the Arctic Cat headliner and hard top. I bought a Fusion headunit, which has a built-in Ipod dock inside (really like the size of the buttons and the display on the Fusion; marine stereo and speakers definitely the way to go, more for dust than water here in Nevada). I have 5" Poly Planar triaxials up front, and 6" Poly Planar triaxials in back. Had to fab a support brace for the rear of the stereo (towards the front of the Prowler) out of 1/8" x 1" flat bar; this bolts to the back of the stereo and to the x-brace/roll cage. Also installed a Sirius tuner; right now running the antenna on the outside of the cage.
Had one issue with wiring: decided to use the auxilliary jack that is on the right side of the shifter. However, had lots of ground issues this way, probably because I could not find an OEM connector, so I tried bullet connectors. These work fine for the power side, but not a good enough ground. I re-configured the ground, using those cowboy type connectors, and it works fine.
A couple photos at Photobucket:
Happy trails!
Bob