What modifications are needed to make the lower rear aluminum control arms for a mark 8 fit our cars, and what would it take to make the differential fit-I just bought another cast iron with 3:27's, so i may not go that route, but let me know anyway-also, if anyone wants it and i decide not to use it, i can get one fro the local salvage yard with 3:07s i believe-axle code 7?