Rebels

I need to know some things about creating rebel armies. I've seen pieces of these information all around but can't find it all together and organised.

* Sub-faction - what is its role? Does it have to be same as culture in descr_regions or as faction creator in descr_strat or neither (assuming I'm putting the rebel army into a town)?
* Names - how do I pick the name for rebel general, depending on the sub-faction or something else?
* Units - how do I know which units I can use for which rebel army?
* Rebel factions - do they get assigned automatically depending on the region rebels are put in?
* An easy way to find out X,Y coordinates of towns??? I know a few ways to find that out but neither is very practical.

For co-ordinates use the show_cursorstat command in the console.

For a list of vanilla town co-ordinates compiled by Swfartir see here:
https://forums.totalwar.org/vb/showthread.php?t=50921
.