That's very much how my Holden Scurry is!
No room anywhere under the engine compartment, so we mounted it under the vehicle, about 1 1/2' back from the engine.
The turbo was too big (or so we thought!) as it was off a 2.5L engine, and the slurry is not even a litre. :)
We ran a exhaust pipe from the std manifold on the left hand side, to the right hand side, and almongst other bits and pieces, it is PERFECT!.
Could not have sized it better, no lag, good top end, better on fuel, better driveability, lots better performance, I can't believe I didn't do it earlier!