Dell 2162DS KVM - Inner Rail Kit

Hi all,

I have a Dell 2162DS KVM Switch that works well enough.  While it has inner rails attached, I am trying to figure out which inner rack rail set I need to install.  I have a Dell square-hole 42U rack.  I probably won't be sliding in or out, but it appears with how the inner rails are attached they clearly want to slide into an inner rail and I can't see any way to mount with just ears.  All help appreciated.