Territory Campaign?

[A-Train]

Has anyone come up with a basic idea for a territory based campaign to go with Flying Lead? Basically what I'm trying to do is near Future gangs battling over a city. There would be a map something like

11022
11022
00000
33044
33044

With 0 meaning neutral territory and all other numbers being linked to a gang.

I don't have a lot of gaming experience so if there is another game otu there that I could steal the campaign rules from, to combine with Flying Lead I'd be most appreciative. It doesn't need to be very detailed, if there's nothing out there, I can come up with something myself. Just would rather not reinvent the wheel.

Thanks

[richjones]

There is a campaign system that could be adapted in the Afghan supplement Hearts and Minds