Not sure if just my mods, but there is one far right corner at the edge of the city map. It is also a spawn

There are 6 gas stations on the map.
In the suburbs (green zone), a gas station is located opposite two large buildings, a restaurant and a kindergarten.
One is in the port (yellow zone)
One is located outside the city, in the upper right corner
The other three gas stations are located in the urban (red) zone.

Map in high resolution, on the site (link in the description), look for words - full map in 22k