Here is Pontiac procedure
REMOVE DOOR PANEL
Yes it is supposed to slide towards the rear of the door, "slightly" into the groove of the flat "lock" piece that is holding it on the inside.You may have to reach inside & hold the flat lock piece from moving.If you do not have the Door Panel off, you will need to remove it
it's off, i'm just not understanding how this is supposed to slide out like that. what is the flat lock piece?
Once you get the Torque Screws out, you slide the handle thru the groove in the door (flat lock piece) But only about half way, to pull handle out