Stillen i think had one in development, but canned it. I fabbed a saleen onto mine, so I know its possible dimension-wise. You will have a lot of fabbing to do, but if you know tools, it shouldnt be that hard to do in a days work.
Get a takeoff grill from any of the take off sites, and use the stock honeycomb v6 grill surround as a spacer( you have to cut it). The dimensions should add up.