The Gc would move swiftly with any late model conversion....But $16k!!
There was reliability before 6 speeds.....
Alternately save your bickies, Buy Tidee's 4.44 Sti box & rear diff ($1200).
NEW factory 207 bottom end ($2900 with gaskets),
recon your heads ($1k)
New oil pump ($150)
add an
ecu ($1k),
add some cams (<$600)
Add a china spec Td05-18g ($600)
Tune $500........
End result will be a reliable daily with 280-320hp at the hubs.....With the ability to have the wick turned up if you want more grunt.
Plus The motor is brand new.
P.s It will be damn quick!