Thanks everyone for your kind words. I just posted Part II on building the 3DR "Simple" delta printer: [trains.socha.com]. I've also updated Part I because I realized I was missing some parts in the parts list.
One thing I should note is that I'm using the hobbed bolt that came with my original V1 Printrbot Simple, rather than the V2 drive gear. The hobbed bolt and geared extruder seem to provide more than enough force to push the filament through the Bowden tube. I have doubts that the V2 drive gear would work well enough, but I haven't tried it. Also, the hobbed bolt works with Wade's extruder, whereas I'd have to modify the design to work with the V2 drive gear.
One thing I should note is that I'm using the hobbed bolt that came with my original V1 Printrbot Simple, rather than the V2 drive gear. The hobbed bolt and geared extruder seem to provide more than enough force to push the filament through the Bowden tube. I have doubts that the V2 drive gear would work well enough, but I haven't tried it. Also, the hobbed bolt works with Wade's extruder, whereas I'd have to modify the design to work with the V2 drive gear.