Sorry, I forgot the 93 cobra got rear discs.The axle shaft off a cobra is longer by about 3/4" Won't work with drum brakes.
Unless you mean you bought the entire rear axle with the disk brakes
You can swap an entire sn/95 8.8 in. Direct replacement. Disc brakes and 5 lug rear in one shot. I have found those rear ends before for $100 at the scrap yard, you would just need 5 lug rims for the rear.
Chris