I just did Boundary over the July 4th weekend.
> We will probably be travelling in a 2WD Toyota Tundra.
Should be fine. I'd say high clearence is almost required, 4WD isn't. Most of the road is well graded, but a few spots are ditched enought that I'd worry about bottoming out a passenger car.
> 1) How much water do folks take for the hike? We like to take a little more than we expect to use. 3 quarts / person? 4 Qts? more?
I took 4 qts (I hate running out of water) and used about 2. I also started pretty early so did all the valley walking before sunrise.
> 2) When we get to the trailhead, is there any way to really really confirm that we are that trailhead? I'm afraid of taking a wrong turn and ending up at the end of the wrong gravel road. Is there a sign, spot-a-pot, or something unique at that trailhead.
There's a Boundary Peak sign at the trailhead. I've got a photo on my website at:
http://mcfarren.info/adam/outdoor/highpoints/nv/nv-Pages/Image1.html
> 3) Is it reasonable to start the hike before dawn if we have good flashlights & headlamps and we scout out the first 200 yrds the day before?
Definitely. I had just flown and driven from 800ft to the trailhead, so I wasn't sleeping very well and decided to quit pretending to sleep and started hiking around 4am.
> 4) How long should the drive take from the highway to the trailhead?
About 40 minutes.
My whole trip report is at:
http://mcfarren.info/adam/outdoor/highpoints/nv.shtml
Let me know if you have any more questions.
-adam