I find it pretty easy to just make up a hitch / ball combo for each of my trailers, and carry that under the back set of my truck. Once you get past three trailers, you usually find that one you already have made up for one trailer will fit another, so usually we're not looking at more than maybe three or four different combinations. Right now, I actually only have two hitches and three trailers, one being a 6" or 7" drop with a 2" ball and the other being a 4" or 5" drop with a 1-7/8" ball. Both are greased, wearing a condom, and stowed under the back seat where my shin will never accidentally find them in the dark.
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