Ok with about 6-8 hours of trimming, grinding, and filing I got them to fit, so I've got a 1 of a kind mod on my car. I could probably do it a little quicker if I did them again, but I was removing small amounts at a time, and working out what looked best.
I snapped a few pics to show them on, and then took them back off. I'm painting them at the moment and I'll get some good pics later. I'll make a thread and post a link, but till then, here's the unpainted louvers on an unwashed '12 (unwashed has been pretty rare for this car, but rained last night and is raining again as I type).