Going from my '06 here but the figure above looks identical to mine...
There will be some screws to remove... typically they are T20 or T25 Torx. Look for one on the tilt lever, which has to be removed to get the bottom half off, another one right next to the tilt lever, and at least one (but probably two) more on the very bottom, one of which usually "clamps" the two halves together... meaning, if you get everything "loose" (snaps, etc. ) but they just won't come completely apart... look for another screw on the bottom.
Kind of an un-neccessary pita, getting the two halves to snap apart (hard/no place to get any leverage). Cover the ears of all youngsters before you start...
If it were up to me, I'd remove the bottom panel under the steering column 1st. It snaps out at the top (corners and sides) and has screws on the bottom (very easy). That would give you a place to fish around 1st, then if you can't find it, you'll have a way to grasp the lower shroud while pulling (or trying to pull) them apart. The structural member that holds your hood release lever is seperate and behind the plastic panel. It is also easy to remove (screw or nut driver) and will give you full access to the area I think you need to get to.
Famous last words... It is doubtful you could set off the airbag doing this. If the quarter fell between the upper shroud and the instrument panel then the only things it could interfere with are the tilt mechanism or the shift lever (if it's an auto) and even then it would have to sit just right. There isn't anything that could "short out". It's a lot less complicated in there than it looks from the outside. The clockspring is right behind the wheel itself and is presumably (hopefully???) well protected from just such a condition (by design???).