help?hole in the firewall,where is it?

i have a 93 civic coupe and i need to find at least three 1/2" holes through the firewall. i found one near the accelator but that is enough to run one hose, oh i forgot to say that i am installing air rod system on my car i just needed to know if there were other holes in the firewall that i can get too with out drilling a hole just yet.