hello everyone, im in the process of adding the track to a Campbells through plate girrder bridge and have a question. is it more proto typical to add a spike on every tie or to just place them every so often? also, do most of these type bridges have a guard rail on them? i was planning on installing the guard rails, but wanted to make sure. if anyone has any pictures of this type of bridge, it would really help me, i cant seem to find a close up of any. thanks!