Not sure about S.A.; but in VIC if a car is caught with any part of a NOS kit installed, a fine of $2000 per cylinder applies. That's right $12,000 for our cars. If this is an EPA issue (not roadworthy) then i dare say the fine applies nation wide.
Not to burst your bubble, but is 24rwkw really worth the risk? Especially when a 100% standard GTT produces that power and probably a little more. Put an exhaust, fmic, Pfc and some more boost, on a GTT, and you wont be anywhere to be seen .