I think I can do the front two nuts with the mini ratchet + short extension.
With the rear one, I can get my "screwdriver" onto it but it's near impossible to grip. I can see it from the top of the engine bay and there's nothing blocking the path to it, so a suitable frankenstein mix of (long) extension bars and possibly adaptors should do the trick... which of course I don't have.
Time to reinstall the airbox & tubing AGAIN and go for a drive AGAIN to get more bits then wait AGAIN for the engine to cool.
Oh, it gets better. Father in law just called and needs his socket set back, so I have no way to remove the airbox now. Guess I'm leaving it for a few days because it will be raining tomorrow. What's gonna go wrong next?