I recently had to do the same repair.
Getting the black plastic duct out is a pain.
I think swearing and yanking was what finally removed it for me !!
You actually have to exert enough force to deform it slightly if i remember correctly.
I think i pushed the whole thing down a bit, then pulled the top towards the passenger side.
Enjoy pulling it out, because getting it back into place will be even more frustrating!
When you are done, enjoy the heat and the fact that the repair only cost 5 cents for a screw.