Did the stepside bed rails have 4 holes on top

[Gregski]

so I listed my stepside bed for sale on Craigslist and a potential buyer posed a question if it had any extra holes in it, when I went to take a look I told him there were four holes on the top of the bed rails which to me looked very even factory like, so since I never ran this bed myself I am asking you guys if these could have been standard holes from the factory

[Danmcg]

The factory rails would have pairs of holes for the mount brackets.