Are you swapping the entire axle with the disk brakes? If so, that axle is 1.25" wider EACH side...so 2.5" wider overall. Also, the axle mounting points are a different size bolt than the 86-98 axle. They went from 12mm bolts in 86-98 to 14mm bolts in 1999, so this needs to be addressed as well.
If offset isa concern, keep your original axle, swap the disk brakes over to it, and run 94-98 axle shafts
Are you swapping the entire axle with the disk brakes? If so, that axle is 1.25" wider EACH side...so 2.5" wider overall. Also, the axle mounting points are a different size bolt than the 86-98 axle. They went from 12mm bolts in 86-98 to 14mm bolts in 1999, so this needs to be addressed as well.
If offset isa concern, keep your original axle, swap the disk brakes over to it, and run 94-98 axle shafts