gateways and road_joiners

I have been looking in the data/ settlement_ plans folder at text files for the different factions. Some match, some don't. How are the coordinates between the gateway and the road joiner supposed to line up? Is it if the gateway is set to face north that the road joiner is supposed to be set south? How are the x,y coordinates between the two supposed to line up? Thank you for any input.

This might be helpful: all settlement plans are be reversed 180 degrees in the game from the way they are defined in the settlement plan. So, a building you define to be in the south, in the game will be in the north.