I don't know the hymn you are referring to, but it must have been in the complete accompaniment or choir version of the People's Mass Book by WLSM (World Library of Sacred Music). I have in front of me a 1964 copy of the white - Abridged Edition - Voice Book. It has hymn V-15 followed by Z-4. Evidently, your hymn would have gone somewhere between those two. I know that a brown version of this hymnal came out a few years later, but I don't recall if it was more complete or not.
While we're into evening hymns, I can't help recommending Christ, Mighty Saviour to the tune Innisfree Farm, or O Blest Creator set to Bromley, or The Day Thou Gavest set to St. Clement.
I think I may have the accompaniment version of the People's Mass Book by World Library of Sacred Music in a closet at church, (I'm always finding things -- 4 modern notation copies of the Liber Usualis under a stack of Christmas Carol for Tuba arrangements, recently ....) I' will check on Saturday, if that's soon enough, Father.
To participate in the discussions on Catholic church music, sign in or register as a forum member, The forum is a project of the Church Music Association of America.