If you want steering controls and temp/fan controls back there is this thing called the PAC-SWX. It hooks up to the steering wheel wire and then if you have a deck with IR and you have the remote you can program any of the stereo buttons to do whatever you want on the stereo. It will also re-enable the climate buttons. Its about $40 on buy.com.

After installing this the only thing that won't work will be the date function in the DIC.

Whoops, this was supposed to go in another thread, but it may be good to know anyways. Sorry.