Check to make sure the bolt pattern where the wheels mount is the one you want. The trucks used at least two different patters depending on the year and application. (2 or 4 wheel drive)

I believe there were some 1984 trucks built with both the small and large bolt patterns.

If you want to switch bolt patterns, you can do so fairly easily on the two wheel drive trucks. I believe all that is required to change the front is to buy rotors with the correct pattern.

It is also possible to switch axle shafts in the rear axle to switch patterns. I haven't done this, but know it can be done.