Radio, Steering Wheel controls

This interior is quite nice, but what I'm interested in is the aftermarket radio. Does it still work with the steering wheel controls? Also, is it possible to add these steering wheel controls to a EX model that didn't come with them standard?

Also, can the same be done with the Climate controls?

yes, you just get a harness that's compatible.. i've also seen some harnesses hook up to a small box that will send infrared to the head unit.. kinda cheezy, but it works.