I heard that a F-350 in 98 had factory rear disc brakes and was still standard 8 lug pattern. I think in 99 they went to 10.50 with metric. I have a 97 with a 10.25 that needs better brakes. If the did it factory in 98 I should be able to order the parts to do a factory swap and end up with a good e-brake. This is a tow rig and emergency stops are scary when towing the bronco.