Like stones mentioned, the scoop is just directing cooler air into the box so a new tune would not be required.
Although I too, never use the washer fluid, it is technically a requirement for PA's safety inspection. (You may want to check with your state too)
With that, I have the same setup as hesster with the tank mounted on the air scoop and the filler tube mounted to the CAI box. I happened to have the front bumper off at the time for other projects, but it is not required for this install. If you do go with this setup, it is a lot easier to mount the tank to the scoop first, and then install it on the car.
