there are 4 points where the trim snaps on/off, two on the bottom and 1 on each side at the top. I used a extra wide screw driver and put a rag/cloth over the tip of it so i didnt scratch anything and so that the corners didnt poke through. i gently wedged the driver into the bottom corner being sure not to gash the bottom plastic and pryed slowly untill the corner popped out. then i ran my finger under the bottom edge to pop out the other coner then the top corners. as for the stereo its held in with 4 screws. i used the scoche wiring harnes specifically for the 07/08 aveo sedan.
o ya and after you get the stereo trim off you can pop the air vents off from the bottom and just pull it out, this will reveal 2 screws for the top/center dash plate. under it there is alot of extra room. I used the space to mount the sirius and usb module's for my alpine head unit