Ok so I'm at the same point with my ke30, however requiring being basically P plate legal for another two years I've narrowed it to either L67 (supercharged ecotec) or a barra 4L.
Having the ability to do basically everything in terms of fab, engine work, electrics etc so hoping for a 'cheap' build but as the saying goes; "estimate cost, then double it"
Anyways OT if you want to do it don't let anyone hold you back. But... Weight/power wise, is it your best option? I do understand the whole idea of using something your familiar with to simplify things.