I have seen multiple nucs made from deeps without much modification.
Typically a divider is placed in the deep, and a strip of wood is added to the
middle bottom board to divide it in two at the same location. Typically a
modified inner cover is also used so one half can be exposed while the other
half is not. The same outer cover is used. Sometimes the entrance is reduced
from the center to make a more obvious separation to the two hives.
You could simply cut down deeps (possibly a way to salvage damaged ones)
but keeping two in one reduces the amount of special equipment needed.
The deep be made to have a removable divider, so the only really special
equipment would be the split inner cover.
I can't say how well they work. I do plan to try it next year.
-Tim