Well...I don't know how to tell you this...Oh yes I do!
I bought the last ADC Turbo kit made - a T3/T4 kit ($6,000). Gonna be one bad-ass 3L turbo SVT in my driveway

. The car's already a lot of fun stock.
There is much talk of a new, lower cost kit soon, so watch this forum. I can't help you with supercharger kits - though the story with those is pretty grim as well.