Hello, can some one shed some light on this? Researching a candidate for purchase. The axle is stamped BL 1110G2. Casting 3894860. According to this site, a 3.07 - 12 bolt Non-posi, on a supposedly matching number Z. Is 3.07 ratio even possible on a Z? Is 12 bolt the only requirement? VIN 124379N585908.