The prop shaft on my 22 Donzi is really deep at like 7" below.
On my 24 Super it was about 5" below but that was a straight V not a round bottom.
I know guys with 24 X 7s that run the prop shaft at 3" below but need 4 or 5 blade props.
My guess is that a Mirage Plus would work on a round bottom Donzi with the prop shaft at 5" below and maybe as high as 4" below. Give one a try; what have you got to loose