Do you mean the stock airbox or the breather tubes that come out of the engine?
If you have a hole in your airbox you'll pretty much need to just get a new one. Are you looking for help on how to remove the airbox? It's pretty easy, but you need to pull the carbs out to do it (and getting carbs out can be tricky). Let me know, I have a video showing how to remove the carbs.
1981 CB750K with 900 cams
90K KM's, rebuilt head, rebuilt carbs, upgraded valve stem seals
My wife's recipe website that I'm trying to help promote:
Strawberries for supper. Yes, I am a lucky man.