Who knows, but anything's easier when it's factored into the original design, rather than retrofitted.
On the broader subject, if Corvette is to have a future other than as sentimental car, and appeal to a new market, IMO it badly needs to modernize. An OHC mid or rear engine would be top of my list for that. However, unless GM already has such a design in a good state of development, I doubt they could produce one as early as 2018.
And you only have to read "All Corvettes Are Red" (the story of the C5 development) to appreciate the perilous path such long term projects have to travel within GM.
