Using wood screws I already had in my garage I put the 4 into a post/tower.
I had thought to use a post topper from Home Depot on the top, but my tower isn't square, so I used more recycled stuff from home. An old square aluminum pan and a piece of wood for 'weight'. I did use some small screws to attach the pan to the wood. Not the prettiest piece of work, but it WILL work and all in all a workable solution.
Now I'll wait until the next band of rain goes through, then dig a hole in my garden and put it in place. I'll follow the directions given and put in some moss and get some night crawlers from the local bait shop. Hopefully by then, I'll actually have more stuff to compost too.