Next, I wiggled and jiggled the wiper arm until it finally came off its spindle. I've placed the new part near the base of the windshield for comparison.
See the plastic grating covering the air plenum, just below the cowl? That needs to come off.
I just gave the grating a swift jerk and it popped off. It's now temporarily resting on the radiator housing.
Remove the old driver's side cowl piece. See the clips on the back? I removed them and put them on the new driver's side cowl piece. I couldn't figure out how to get the black clip out of its holder, so I had to pry it free. You might want to purchase new clips, but I didn't. Luckily, none of the clips broke.
Since I didn't have a fine-tipped slotted screwdriver handy, I used a butter knife to remove the plastic screw caps that hold the passenger's side cowl piece in place. Once they were removed, it came right off.
Because of the way the cowl pieces overlap, you should install the passenger's side piece first. Replace those two screw caps.