How can I roll my ship to align its floor with the floor of a station?

So I'm trying to make an automated ferry that will bounce around between 2 or more stations. To make this work really well, I want the ship to orient itself on the roll axis so that it's idea of "down" matches that of the station it's trying to dock at.

Unfortunately though, my knowledge of the in game API AND my knowledge of trigonometry leave a lot to be desired.

So, my first attempt was recommended to me on Reddit. Have a remote control in the front of the ship, a remote control on one...

How can I roll my ship to align its floor with the floor of a station?