Just fixed mine, sure enough it was off. I did it without removing the wipers; I just turned the car on so the wipers were straight "up." I shut the car down and maneuvered the cowl (one piece) enough so i could pull off the deflector, put on RTV and reattach the deflector. I tried to take the wipers off but they would barely budge. When I was finished, I just turned the wipers off and let them set in the down position, and whacked them a time or two with a mallet and tightened the bolts down. I don't remember removing the wipers when I had to do the same thing on my Impala, either.
