There easy to do, take the hat off, injection lines at the pump and the two bolts out of the intake that hold the injection lines brackes so you can move them up a tad to gain clearence, just unscrew the holders and take them out with the spring that's inside then fish the DV out with a magnet, older pump(I believe) have little tin holders under the DV's, and you will(or should) have new O-rings to go on the holders and just put it all back togther and T/Q the holders to 85ft/lbs.
Jim