Hi
Your correct, I needed to move the motor & trans forward because of the lenght of the overall package, if you look at the photo of my motor you can see the lump on the left rear cam cover. I have seen SOHC motors in bugs before they fit nicley.
I read an article on a Aussie Subaru STI here
http://autospeed.drive.com.au/cms/A_1824/article.html
that had a few upgrades, nothing much, better exhaust, piggyback EFI controller etc and it made 195 kW (261.5 hp) at the 4 wheels. I will do these upgrades before I put car on the road and then see if I need anymore power after that.
Steve
PS If you cant open the file at Autopseed let me know.