Long Distance Competition/Ultracycling, Randonneuring and Endurance Cycling - 1st century

I am planning on riding my first century this weekend. I have two courses mapped out to my inlaws house. My longest ride yet has been a little over 40. But I commute 21 mile rt ~4 days a week. The biggest el change has been ~400ft. As you can see by the routes below it is a little hilly. The roads are state roads with 55+ mph traffic. Route A is less traffic with a smaller shoulder. Route B has a 4-5 ft shoulder but high volume of traffic. No one is use to seeing bikes on either route. I am planning on starting early to get out of the highest volume of traffic which is the first 20 miles. I am going to make a day of it. But I will be riding alone and a lot of areas do not have anything for miles, even cell phone is blacked out through most of it.

Is it stupid to try and do this by myself?

which route do you think would be best?

Route A http://www.toporoute.com/cgi-bin/getSavedRoute.cgi?routeKey=AHNJQFMNDHMYHHE

Route B http://www.toporoute.com/cgi-bin/getSavedRoute.cgi?routeKey=JGBESBIWCXNODKX

Thanks

Given that you've never done a ride anywhere near 100 miles, I'd say doing it on those roads with the traffic and no gas stations or anything else (and no cell phone service) is not smart. I wouldn't do it until you're able to do at least 70+ miles on a ride.