Do i have to take the kingpins apart on a 1977 Ford F-250 4 wheel drive replace front you joints?

No, you typically do *not* have to remove the kingpins to replace the front U-joints on a 1977 Ford F-250 4x4. The U-joints are located in the driveshafts, which are separate components from the kingpins (which are part of the front axle). You'll need to disconnect the driveshafts from the differential and the U-joints can then be replaced.