eject a single ship from shipyard

Since no one else has asked this question I assume I am missing something very obvious.  I have a shipyard (Yor) with 4 colony ships and 4 constructors.  I am trying to eject less than all ships but cannot find a way to do it.  I can click on "eject all" and it will allow me to assign population to each and every ship one at a time by selecting the citizen then hitting next, but how do I select a single ship, add the pop and eject?