"Build a cargo station on the side of a hill then attach a second cargo building to the drop side of the side (right-hand looking at the image) and then attempt to connect a cargo truck station.

The new truck station would not sit at the correct level until I used the flatten tool to extend a small amount of flat land alongside the rail station. Once that was done I could then attach the truck stop - you can see the blue connection indicators.

Getting the road down to the town, of course is a whole different matter!"