Actors in the Credits

I'm trying to figure out which characters are which. In the beginning there are four hoodlums, one of them simply called "Red" in the credits. Who are the other three?

Red is the red-hooded leader of the hoodlums.

George is the man who enters the convenience store, is attacked, transformed into a zombie, and attacks the hoodlums.

Rhodes is the member of the militia who is giving the orders, and Hess is the older militia member who speaks to Rhodes.

Who is Clyde?

Bonnie is the zombie that Ben encounters in the car.

Eve is the zombie that George encounters at the store.

Who is Gizmo?

Hammer, Slugger, Blade, and Smiler are all hoodlums.

Gibbs is a member of the militia.

Who is John Doe?

Bleeder?
Lurcher?
Johnson?
Headwound?

West is a member of the militia.

Who is Flip?

Militia Driver is presumably the one with the ski mask.

Who is Beecham?

Who is Leigh?

When did Barbara appear? She was only mentioned by Ben as far as I remember.