After a lot of research I've decided to go with the Garmin Edge 1000 GPS cycling computer.
Purchased from Amazon, below are the features that appealed to me.

• Large 3.0" Display - See what you need with ease, and stay focused on the road ahead. Edge 1000 uses a glove-friendly, touchscreen Display that adjusts automatically for low-light areas, such as shade and tunnels
• Smart Notifications - See your text, email and call Notifications from your iPhone 4s or later while riding
• Bike-Specific Navigation -Navigate the best cycling roads with preloaded maps and points of interest (POIs). Round-trip Routing makes it easy to explore new roads, and Route Planner allows you to create routes using the map or POIs directly on the device.

It's going to be mighty hot on my ride and staying hydrated is a big concern. I want to say a BIG THANK YOU to Diane and Cameron at S.P. Richards for the Propel beverage mix. They are small, lightweight and will help replenish electrolytes and vitamins!
​Thanks so much Diane and Cameron :)

After a lot of thought and conversations, I have decided to change my route. I follow a guy on youtube that tours the country in his rv. About a week ago he started his most recent journey taking Route 66 just as I was planning. Not even out of California yet he has already come across several road closures causing him to backtrack to the interstate to get around the closures. This coupled with the extreme temperatures in June and July when I would be going through, I am changing my route to the TransAm route (see image). This is a much longer route but will be cooler and should have less issues regarding road closures. Another benefit of this route is that it goes through my brother's home state of Colorado where perhaps his kids and my other brother can join me for that portion of the ride :)

Thinking about doing something spectacular? Go for it!