To convert a city of a faction in rebeld

[Poulp']

I'm making you the "tutorial"
hang on, I'll be back soon

All right
first, MAKE A BACK UP of the files you mod

then, open your descr_strat folder and find this:

settlement
{
level city
region Sicilia_Graecus

year_founded 0
population 6000
plan_set default_set
faction_creator macedon
building
{
type core_building governors_palace
}
bla bla bla
building
{
type defenses stone_wall
}
}

copy/paste it in the rebel part (bottom of the file)

now, you must deal with the general in Syracuse, I assume you want to keep it into the ruling family (way simpler)

character Dionysios of Sparta, named character, age 34, , x 106, y 44
traits GoodCommander 1 , Intelligent 1 , GoodAdministrator 2
ancillaries brilliant_inventor, playwright
army
unit greek general's guard cavalry early exp 1 armour 0 weapon_lvl 0
unit greek hoplite exp 0 armour 0 weapon_lvl 0
unit greek hoplite militia exp 0 armour 0 weapon_lvl 0
unit greek hoplite militia exp 0 armour 0 weapon_lvl 0
unit greek archer exp 0 armour 0 weapon_lvl 0
unit greek peltast exp 0 armour 0 weapon_lvl 0
unit greek hoplite exp 0 armour 0 weapon_lvl 0

let's place your general near Sparta instead
notice that I've only changed changed the coordinates were he should be, you don't have to copy paste that part:

character Dionysios of Sparta, named character, age 34, , x 137, y 46
traits GoodCommander 1 , Intelligent 1 , GoodAdministrator 2
ancillaries brilliant_inventor, playwright
army
unit greek general's guard cavalry early exp 1 armour 0 weapon_lvl 0

now, let's make the Syracusian army rebel
cut the syracusian parmy and paste it into the rebel part (below rebel provinces)

character sub_faction greek_cities, Phillip, general, age 20, , x 106, y 44
army
unit greek hoplite exp 0 armour 0 weapon_lvl 0
unit greek hoplite militia exp 0 armour 0 weapon_lvl 0
unit greek hoplite militia exp 0 armour 0 weapon_lvl 0
unit greek archer exp 0 armour 0 weapon_lvl 0
unit greek peltast exp 0 armour 0 weapon_lvl 0
unit greek hoplite exp 0 armour 0 weapon_lvl 0

I've created a dummy general and named him Phillip because I was lazy finding a greek name
that should do the trick
did you understand the mechanics beneath it ?

oh yeah

cut your rome/world/map/base/rome.rwm files into your back up
since you're changing province ownership you have to reset your rome.rwm

If that modding doesn"t work, just put back your back ups