Mmm.Mm. Aw man. A 'head' comes from around the square rigger days when the crew crapped off of the sprit of the boat, as Jabsco didn't make good enough macerator pumps back then, ie: the head of the boat. I personally don't like doing it at all off the pulpit, my legs go asleep on the rail. The stern pushpit is much better. Your knees hook comfortably across the first rail, and the top rail is left for a handle. This works great except new marinas. After a couple of times of this they tend to leave you alone anyhow..
I wonder why Jabsco, Johnson Pump, Groco, Raritan, Thetford, whatever calls them toilets. However, I pee in the kitchen sink. Flat footed and proud. Saves water, and the kids get a kick out of it too. And save your money buying those cheesy macerator pumps. I have better luck with a common food disposal like for home use. Hooks simply to 110 volts out of the inverter, and a chopping we go baby. Ammunition, M.R.E.'s, whole entire rolls of Bounty Paper Towels is no match. (That reminds me, now I think I remember what happened to my boat hook). So anyways, Fat Tonys Pizza with barbequed chicken and jalapeno peppers is nothing for this bad boy.
And really, just break down and do the sensible thing and get a stainless steel commode like we used to use in prison. Hell, I've seen Big Tyrone smash one with a fire extinguisher for over three hours before he was subdued..