^ Ditto! There a bit harder to see down there, though my JVX system has a an an adjustable 'slanting' front so it tilts up towards me.
Take the tray out, so you've got the 2 din slots. Plug in your new headunit and slide it on the bottom shelf, because the tray isn't there you can push the wires out of the way as you slide the h/u in. Then just pop the tray in