Steve,
I know the campground you will be staying at. Unfortunately my group will be departing as you are arriving. Too bad. I would have enjoyed having another fancier of the 2 footers to spend time with.
There are plenty of areas where viewing the former ROW is possible. You simply need to know where to look. Right on rte 302 as you head into Bridgton is the tourist office on the left. There are 2 cars sitting out front on a small stretch of track. If you park in the lot adjacent to the cars and walk down the incline behind the tourist office, you will find yourself on the old ROW that lead to the left to the Bridgton station facilities. If you go back to you vehicle and go a bit further into Bridgton, you will find a small gas station on the right across from a school. Park in the lot there and walk down the path to the right of the building. That is more of the ROW that was heading toward Harrison. It is actually walkable (at least it was a year or so ago) all the way to where the bridge that used to span Stevens Brook once stood. On the way to the bridge site you will see the remains of an old trestle that the B&SR used to service a long-gone mill. If you go to Nerail.org photos, look under B for B&SR, you will find many pages of photos that Mike Fox and I have posted of the places I've mentioned plus many, many more. I wish we could have hooked up next month. You would have "gotten your money's worth".