As Spiff and Chip say, you'll likely need a custom area, of something solid, where the tire encroaches on the chassis.
You might have to go high, or low. ANd your resulting 'tube' might be shaped pretty weird. Maybe it's a flattened oval, or even some wedgy/triangle cross section.
I might start by getting a bunch of (don't laugh) gutter downspout parts, elbows, straight sections, adapters and the like, and then I'd mock up the fitment. You can crush and reform those easily and come up with a shape that fits. Then you fab something more permanent with round ends and brackets out of carbon or FG, or alum or whatever, bolt to the chassis, and attach the flex tubes at one, or both ends.
If you decide to go solid all the way to the front air dam, make it multi piece with one sliding into another as you will inevitably move the nose and you don't want to destroy everything in a mild bumping situation. Flex duct is better, if you have the real estate.
