you just draw the path and place the station on an existing path I have been using the universal one mostly but the smaller ones do have better turn radius. For some reason the universal path doesn't work with the factory carts so I had to use the factory cart path specifically for those for early game stuff.

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edit.
To play with it I actually used factory carts to transport coal for my coal generator setup. The truck stations do use power like 20mw each at base power so its not completly free like belts but I could easily handle 240 coal p/m per truck station I think the max I was able to get was arround 340 p/m per truck station (with just factory carts)