Re: 06 Factory Radio to Indash Nav
You certainly need much more than just the bezel.
It's really going to depend on what you are putting in.
If you are going aftermarket you will at minimum need the bezel AND an adapter to make the bezel double-din conformant, antenna adapter, and wiring harness. This is assuming that the radio comes with everything it needs (like the GPS antenna). If you are keeping steering wheel controls, that will require another harness.
If you are throwing in a stock REC unit, you'll need the nav bezel, radio, GPS antenna, and that should be about it.
If you search the forum there are detailed explanations detailing how to go from just about any radio to any radio (including putting newer MyGIG systems into low-speed CANBUS systems), and will detail what is required for each specific install.
You can also check out Crutchfield, which has an excellent website that will tell you exactly what parts you need to make it work.