A Vigil Mass of the Epiphany has been restored in the 2002 edition of the new Roman Missal. The 2002 MR gives the collect as:
Corda nostra, quaesumus, Domini, tuae majestatis splendor illustret, quo mundi hujus tenebras transire valeamus, et perveniamus ad patriam claritatis aeterne.
The Missal of Robert of Jumièges, a favourite of mine, gives the following version for the Vigil:
Corda nostra quaesumus Domine venturae festivitatis splendor illustret, quo mundi hujus tenebris carere valeamus, et perveniamus ad patriam claritatis aeterne.
A good example of where some scholarship after Vatican II has been of far higher calibre than that of the 1948 Commission.
At Mattins the invitatory, hymn, antiphons and psalms are those used for the Circumcision. In the first nocturn the lessons are from the eighth chapter of the Epistle to the Romans with the responsories from the Circumcision. In the second nocturn the lessons are from a sermon by St. Augustine and in the third nocturn the homily is from St. Jerome's commentary on the second chapter of St. Matthew's Gospel. At Lauds and the Hours again the antiphons are those from the Circumcision, O admirabile commercium etc. The chapter is proper to the Vigil, the antiphon on the Benedictus is proper, Dum medium silentium, and the collect is proper, Omnipotens. A commemoration is sung of St. Telesphorus Pope & Martyr.
At the Hours the antiphons of Lauds are sung and the psalmody is festal. At Prime (Pss. 53, 118i, 118ii) the preces are omitted, the lectio brevis is Itaque jam non est servus. The hymns of the Little Hours are sung with the Doxology and melody in honour of the Incarnation.
At Mass, sung after Terce, the Gloria is sung, the second collect is of St. Telesphorus, the third collect of the BVM, Deus, qui salutis. The Credo is sung and the preface is of the Nativity.
Vespers are first Vespers of the Epiphany. The antiphons Ante luciferum genitus etc are sung with the psalms from the First Vespers of the Common of Apostles. The chapter, Surge, illuminare, Jerusalem is from Isaiah, the Office hymn Crudelis Herodes. For the feast and its octave a Doxology in honour of the LORD's manifestation is sung at all hymns of Iambic metre: Jesu, tibi sit gloria, Qui apparuisti Gentibus, Cum Patre, et almo Spiritu, In sempiterna saecula.
In the 'liturgical books of 1962' the Vigil is abolished and the day is another fourth class feria of Christmastide. Mattins has one nocturn and three lessons. St. Telesphorus is commemorated at Lauds and said Masses but with the collect Gregem tuum from the Pian fiddlings with the Commons. The hymns of the Little Hours are sung without the Doxology of the Incarnation. Vespers are the same as the Old Rite. At Compline Te lucis is sung without the proper Doxology.