Nice work! If I ever get locked out of my house, I know who to call.
However, your explanation doesn't answer why you could only insert the key halfway before... Were you able to insert the key fully after opening the glovebox, or did that issue persist?
Removing the center vent sucks. When you find the directions, don't follow them... Some steps are missing and some are totally incorrect. I think the key is to remove the stereo and get at an unmentioned fastener at the far left of the vent, otherwise you're sure to shatter it upon removal. The rest of the discrepancies you can work your way through with some harmless trial and error, which you're obviously pretty adept at.