This kind-of goes along with the engine swap thread under another heading.
SAW took the (relatively) easier way out by utilizing the entire Subaru drive train; tranny, half-shafts and all, which puts the engine over the axle centerline, and, hence, into the back seat, just like the Fierro guys did. This improves the weight distribution and all that, and it even gives you more trunk/stowage space, but at the cost of losing the rear seat AND having potentially increased engine noise (bearing in mind that, with the cylinder water jackets, it'll probably be quite a bit quieter than an aircooled).
Having typed all that, I would STILL be more than a lot intrigued with the idea of a 'glass 356C coupe, with a beefed up VW transaxle mated to a 150 - 175 hp Subaru engine in the rear. Why a "C" version? Dual engine cover grills under which to mount the engine radiator (ducting would be needed, but would be easier with no engine fan shroud in the way). OK, so you could run an "A" body with a "C" style engine cover if you must, but it really sounds like an easy conversion. If I got my son and his Eclipse friends together on this I bet we could have it done in a week or less (no kidding, they're THAT good), ESPECIALLY if KEP has the conversion kit already done.
Now, all we need is for Carey to get that Envemo Coupe kit into production and we're ready to Rock!
GN