I had the guys run one feed to a central location, mount a 3 or 4 gang electrical box and then bring individual runs out to logical clusters. As long as the splice point is marked on the prints, troubleshooting is very easy.
And with that many speakers, you'll want the two most important pieces of test gear available - an impedance meter and an iPod. With those two you can get anything working.
Two excellent suggestions Sam. I'd also second Atlas Sound for a source of 8" speakers without grilles. The model C5AT70 is probably exactly what you are looking for.
Your local Dukane Sound dealer is Life Safety Solutions (
https://tlglss.com/educational.asp) and I am sure they'd be happy to quote you on the model 5A607 speaker which is exactly what you need!
