Looks like you can cut the header panel backing piece back to just under where the support bracket mounts? Then leave a piece to the left and right side and cut openings for the side vents. Still looks like it hits an air dam at the mounting bracket but it should allow the air to dump into the IC area.
Nice pics, thanks for the work and info, should be "fun" to do the install.
Nice pics, thanks for the work and info, should be "fun" to do the install.