I'm not to clued up on the engine in particular, I'm sure others on here that know them like the back of their hand will be able to
help more.
However, I'd say the engine is not best suited to turbocharging. The 8v just runs out of puff too quickly (well, mine does!). With only those two valves it just can't shift the air fast enough at high revs, and bolting a turbo on it is just going to make it even worse. Unless you go for a lp turbo, when you'd have a stonking mid-range, but would it be worth the hassle? Doubt it.
With the manifold being at the back of the engine you may be hard pushed to physically fit a blower in as well, considering how far back in the engine bay the block already sits? Then you've got to sort out an intercooler, lower the compression ratio, sort the fueling and get all the plumbing made up!
Far easier to drop in a unit desinged for a blower in the first place, VAG have a few to choose from
