Ok, first of all, what have you found?
That said, they did use their own air cleaner, I do not have any photos of them, they are pretty rare. So far for 1970, I know of two Hemi Challengers that came with the N94 hood, one 383 R/T and one Challenger 340. I have heard of two cars with it in 1971 also.
I saw a photo of the Hemi base online someplace, I will try and find it again.
T/Ake care,
Barry