I also think you can do it.
Try to eat a little on an ongoing basis - I would generally eat something every 30 minutes or so when I started doing centuries (I get most of my calories in liquid form so it doesn't apply now). You want to have a steady stream of calories without ever feeling full.
Avoid foods with a lot of fat, as they can cause stomach upset.
As for pace, try to ride the "I can ride all day at this speed" pace, and don't push yourself on hills.
Finally, see if you can meet other riders with a similar pace on the road, and ride with them. The miles go by much faster if you can spend some time with other riders.
Good luck.