On the map above, near parking #1 (in kinda the lower right hand side of the map) there's a white box that says rental cars. From there, you can easily go along from north-ish end parking garage 1 and the rental car return traveling north along a covered walkway towards parking garage 2, hang a right and go across the bridge over the road from the southern-ish end of parking garage 2 to the terminal. I've never timed it, but I'd be surprised if it's more than a five minute trip. It's easy and well-signed.