Peco Bridge Construction

[4073]

This may be a simple question but could someone let me know where these parts belong?

I am constructing a Peco Lineside Bridge, I know where the winged retaining walls are fitted but what about the Parapet wall & coping stones shown at the top of the photo?

Do these fit on the back of the bridge i.e. roadside? 

Any help is greatly appreciated, thank you very much

[JSModels]

Yes, the middle piece in your pic goes on the back (road side) with the top edges flush. Then the coping stones go on top.

[4073]

Thank you very much for you help