Okay, chiming in here...
first of all, cool car...
If you must put a wing on there...and its the wing you already have, go edge mount for looks and less stress on a smaller area of the trunk....I would think you would want better distribution along a larger area... (I know, the wing does not weigh that much, nor will it generate THAT much downforce...but...)
On a totally subjective and personal note, I would opt for the same wing, but shorter supports....I agree with the comment about your cars overall look....bad ass...is still too stock to put a wing that big on there.....just MHO, though, to each his own!
either way, go for it...its just 4 holes, right?
JP