you'll need to get an RX3/ FB RX7 crossmember and retrofit it into place over your swaybar mounts. you'll also need a custom gearbox crossmember, exhaust and tailshaft. the clutch is hyrdraulic on the rotary box, and the 1200 is cable operated. then you'll find the brakes need 'more', and you'll get pissed off at diff's snapping every roundabout. you'll also want to get a hold of a rotary vehicle's radiator, the RX4 is the best of the lot, but the FB RX7 is plenty big. and for god's sake, don't forget the small little oil cooler under the radiator.

other than that, with those crossmember pieces, it's a fairly straightforward conversion - and the ease of screwing power out of a rotor makes the conversion very appealing.

good luck.