I did the trip last year with a couple of others. Brian Kelly (Irishtothemax) pretty much put the trip together. Unfortunately, he died this past spring. I will be happy to answer any questions you may have and I'm sure there are others who will do the same. Here's a link to our trip. Hope this helps:
http://www.jbriankelly.com/Route 66/66index.htm
If you would like to PM me, I'll be happy go over the trip with you. I don't know when you are planning to come but I would suggest you try to get here for Spyderfest, April 23-29. You can get the details here on Spyderlovers. It is held in Cuba, Missouri, which is right on route 66. This is where we started our trip last year instead of Chicago since route 66 in Illinois is pretty much a regular road. There will be several hundred Spyders at Spyderfest plus the host is one of the top, if not the top, Spyder dealers in the country. You will meet lots of great people here who will help you start your trip. Spring is a good time to do this trip as it has not gotten too hot in the American southwest. You may hit some rain though but who knows.
Dick