rg, thank you so much for your timely post.
After seeing the video a few months ago, I bought some tubing and set up a bunyip using 6' metal fence posts that were at the farm. This was just a very quick set-up to show the idea to Sis and BIL when they made a trip down to help put everything up for the year. We took some time to look at contour in the camping area and talked about what modifications would have to happen before spring. On my list of things to do today is pick up an extra few 2X4's and make sure the wood-burning set is handy. After marking a couple of 2X4's I plan to split them down the middle. That way each set will match. We discussed using some sort of spike to make it easier for me to use the level when I'm alone. The step on plastic posts look like a low tech way to handle that, at least initially.
I need bunyips not so much (initially) for finding level, as to map out the hillside where I plan to build. Slope in the area is as much as 30% and the length (I bought 40') will be welcome. The RV antifreeze is also a great idea that hadn't come to me yet, but I have some in the garage. The pink should show up well against the snow, or years of leaf duff (if the snow still doesn't happen for a while).