I've heard the horror stories about grease, and pants, and wiping (Oooooo, the wiping!!!) I'm not gonna lie (this time), I have gotten a little grease on my pants once or so, and I do carry a roll of paper shop rags at the ready. If I'm travelling any decent distance, I grease it up pretty well. A dollop on the ball and spread it around, a dab on each of the four contact points on my trunnion head, and a dab of Vasoline on the two bar/cam interfaces. When I get to my destination, the first thing I do after the dust has settled, is wipe down the grease and road dirt off the parts, cover the ball with my custom plastic cover and place all the components in the bed of the truck for the duration of the stay. Takes all of 5 minutes and I'm done and ready for clean hitch up on the way home. Just a hiddeous usage of time and materials, I know.
The bright side is, my parts are beautifully seated, make little or no noise, and will last a looooong time. Ohhh, the horror!