Corbin-Russwin Shackle/Plug Retaining Pin Question

[Robotnik]

I'm currently working with a sub-assembled Russwin padlock, and wanted to make sure I'm on the right track with the lock's body pins. Photo below:



From the C-R padlock catalog, I believe the visible protrusions are the heads of some screws that sit atop the body pins. My question is, when assembling these padlocks, are these heads simply ground down flush with the body, or is there more that needs to occur for a proper job?

Thanks!