It may help you to go to Winnebagoind.com and put in your model. From your post it's not certain whether you want to remove the table top from the rails, or the rails themselves. The rails typically have a plastic tab at each end. One tab goes down, the other side goes up, and then with a little tug the rails come apart from each other, one piece remains in place and the other comes all the way out and remains with the tabletop.
It may help to go to a hardware store and look at rails on the shelf to familiarize yourself with how they separate.