Of course, you'd have to modify cooling (i.e. to conduct the hot air to the outside), Sauber was able to do it btw. M. Kaltenborn also said about this very modification, that in theory their approach to leave last years configuration was based on simulations which showed higgher potential of the Ferrari / McLaren and Sauber early 2013 approach. But in reality, they were never able to exploit the effect and returned to the 2012 ramp style.
Domenicali recently admitted that they never really understood exhaust blowing in the last years, and exhaust blowing is something not that easy to simulate or test in wind tunnel.
This makes me really wonder why we never saw Ferrari at least trying to copy the fastest car on the grid since 2010.