Nice choice of engine!
I have a modded X20XEV sat in the corner of my garage at the moment which I am considering using if I go down the Sierra route.
I'm waiting to see the Saturn MX-5 plans first, although I'm certain which route I go down will depend greatly on the availability of the donor.
Really struggling to find a Sierra for the kind of money I want to pay (not very much)!!
Are you using an Omega Gearbox or a Ford Type9 with the Belhousing adapter?