I dunno hy you would bother if its a ford keep it ford powerd the i6 can produce heaps of power when properly done i have had a worked i6 in an ea ghia heavy car 5sp and 3.45:1 final drive and it imbaresed heaps of v8's.
i currently have an eb xr6 auto and considering a few options.
1. keep it auto and drop a windsor in.
2. doin a bit of minor engine work and turbo and 5spd
3. dunno if this is possible drop in a barra i6 turbo out of an xr6 with a 5spd
but have been quoted for motor with all accesories by ford something like 12k and use aftermarket managment.
Car 1: Eb xr6, Factory power windows & Alpine premium sound
My Mods: Super low kings springs, 17" advanti rims, cold air intake
& Lukey extractors with 2.5" straight through exhaust.
All the money being poured into this one now.
Car 2: Xe esp,383 stroker, c10, 9" diff etc... R.I.P my beast thanks little bro!!!!!!