hi an idea possably ,could be to isue small maps of the site with a compass bearing n the map divided into a grid section for easy n quick co-ordinance calling for non experienced n the pro just to help keep comms pro n running free n easy.
this will help when giving directions by stating a ref not street ect.
JUST A THOUGHT.?

There will be maps given to every player, with a numbered/lettered grid on it.
The two teams will have the same map but with a different grid layout for each.