First you have to make a C beam with these numbers for the whole track length.
Then you end up with a trough like this.
Then you import a second coaster that you make into a 0.3 foot by 0.3 foot rail that you place in the bottom of the trough close to the edge of the through.
Then you have a rail on one side.
Then import that rail again and make the shift negative to put it on the other side.