You’ve been given some good points to consider already. But don’t forget about your wall/pier heights ratio. You don’t want your pier to be to short or you’ll lose those sometimes low objects you might want to capture cause you can’t see over the wall. I actually made an adapter to make the mount higher for my existing 12” pier, I had made for my previous “other brand” mount that was of no comparison to my AP1100, so that when parked my new setup clears the rolling roof with about 5” to spare. A little scary the first few times you open or close the roof when the rafters go passing by, but actually a good distance for safety once you get used to it and “know” it’s not going to hit your camera or telrad or whatever sticks up. I can see all the sky I can see at my location with this height.

Steve