[Panelfantastic]

Stock decklid not possible.
The engine isn't really that big, what kills it for bug installs is that it is both longer (by about a foot) and taller... well not really that much taller but it carries the height the entire length instead of just at the shroud. You would definately have to build a custom decklid, something with a bulge right where the tag goes and modify the rear apron slightly. The apron mod wouldn't be visable with the lid closed.
There may be an Eco bug in the works for me, but not until next year at the earliest.