Make a kit for an E46 and I'll buy one.
In fact I'll even help you if you need help... I have an E46 to take measurements from and can draw up and components you need to have out-sourced to a supplier/machine shop.
Summer: BMW 135i M-Sport
Winter: 2004 Audi A4 Ultrasport 2.7tt
Year round: 6 cylinders, two turbos, and 6 speeds.