Can you take a pic of what it looks like with the cylinder removed? Does the cylinder turn with the key now that it's out of the latch? When I peeked a flashlight around my lock, it looked like moving the key cause a piece of metal to move left and right...probably a disconnector or something for the handle. The lock cylinder is just a keyed turntable so I imagine a flathead screwdriver or maybe 2 opposing flatheads will be able to do the same thing the cylinder does.
OK I figured it out. Was able to remove my lock and pop the glovebox.
You need to get a metal stick of some sort (i have a metal hook/pick set that has a straight pick) and stick it in the red circle and then pry that to the right. Took very little force. Glovebox opened right up.
This is the bottom of the cylinder (the side with the notch)
EDIT: Got my orientation wrong. The side that says SDA/4 is the left side of the cylinder. In the pic the lock is ... locked .... because the key is in line with the text.
And for future internet people: here's how to remove the retaining ring thing. Right angle pick under the black wire with a lifting (twisting) motion:
Reinstalling the cylinder was "shove it in, lift and push the retaining ring back where it was". I didn't have to remove the glovebox...so the service manual is probably being excessive in recommending that (not surprised).