1. Yes it requires an adapter. Basically every aftermarket unit with the exception of a few eclipse units require an adapter. There is one for yours that plugs into the back and works flawlessly vs. the universal PESWIX. I think the part number for yours is SWI-JACK
2. You don't have to hook up the speed sense or reverse wires unless you want to. Speed sense helps your GPS keep you on track if you travel through places with a lot of hills and elevation changes. Reverse is only necessary if you are running a rear-view camera. You can connect the light green (parking brake) wire to the black wire in the harness...illegal but easier.
3. Yes its 2 slots.
4. Drive to me in NC... I'll even give you a hell of a discount.