Sparky--
I wouldn't mess with the d'versibit. It's designed to drill through framing (basically 2-by lumber) and you'll have a problem with chip clearance trying to drill several feet of solid wood. Also, I bet the d'versibit will wander off line and what a mess that'll be.
I'd use a naileater (ship's auger) or an electrician's bit (auger with cutting spur, makes a neater hole). Use a 7/8" or 1" bit, start with a 6", go to an 18", then start adding extentions. Make sure the hex screws on the extentions are tight, and check them occasionally when you pull the drill stack out to clear chips.
To create the cavities for the boxes, I'd use a small chain saw--plunge cut & hog it out. Or use a plunge router and shallow (mobile home) boxes.
I agree, price the job based on $100/hr, and build a new hole hawg (and about 10 bits @ $30 ea) into the bid.
Is the roof on yet? If so, I'd get the stupic GC to remove the shakes or whatever above where you're going to drill down, and drill from above. The GC can have the roofing sub come in and patch sheathing, felt, replace shakes, etc.
Hoo-boy, this is gonna cost! The alternative is to surface-mount the boxes and use wire-mold. Maybe the wire-mold could be covered with a wooden half-round (w/channel routed in back).
Best of luck...
Cliff
