The Eminence pxbii-1K6 crossover is basically identical to your Theater Four Pi design, minus the the several additional components (Zobel, Tweeter attenuation with bypass, ...)

Correct?

When I order all the parts I'll post a listing of parts and costs. I'm looking at about $380 for both speakers (excluding wood, including shipping estimate).

Side Note: I was over at best buy... looked in their speaker section... listened to some big floor standers from several major manufacturers, liked JBL the best, every time I listen to BOSE systems, I like them less, KLH even sounded better. Later that night heard some music playing from some not special looking Yamaha 2-way PA speakers that sounded way better, compression drivers are just the way to go. I'm psyched!