You would make boy # 5 for me. As I would do for any one of my own sons -- if they wanted the best possible option for performance, quality of kit, and ease of construction -- this is where I would point them: http://www.diysoundgroup.com/
This awesome site is the brainchild of our very own Erich H from this forum. Specifically, look at the Waveguide Speaker Kits for LCR/Surround and the flat-pack subwoofer kits (the 4.5 cu.ft. box would readily accept one of the Stereo Integrity or Dayton 18" drivers that are so popular on the forum these days).