I do ours, but it's an older chassis. I mention older because Ford has gone "lifetime sealed" on many parts that used to have either grease fittings or plugs you could install fittings into. For example, our 2002 axle had plugs in the ball joints and the 2012 axle doesn't even have holes for plugs or fittings there.
If it HAS fittings, they'll be tucked into the center of one intersection of the "cross" that the four caps (which go into the driveshaft yokes). Hopefully they line up so one positioning of the driveshaft lets you access all joints at once.
Should be lubed with a hand-operated grease gun and the seal of each cap watched to look for grease just seeping out of all four.
If it doesn't have fittings, I wouldn't hire anybody to dismantle the joints, pack the caps with grease then reassemble.
If God's Your Co-Pilot Move Over, jd
2003 Jayco Escapade 31A on 2002 Ford E450 V10 4R100 218" WB