I can provide links for Chrysostom but not Ambrosiaster.
(Homilies on Romans, Homily 7)
newadvent.org/fathers/210207.htm
(Homilies on 1 Timothy, Homily 4)
ccel.org/ccel/schaff/npnf113.v.iii.v.html
(Homilies on Galatians, Homily 3, Verse 8)
newadvent.org/fathers/23103.htm
(Homilies on Ephesians, Homily 5)
newadvent.org/fathers/230105.htm
(Commentary on the Acts of the Apostles, Homily 32)
ccel.org/ccel/schaff/npnf111.vi.xxxii.html
This is not to say that he did not view good works as important because he also said:
(Homily on Ephesians 4.2.9. Mark J. Edwards, ed., Ancient Christian Commentary on Scripture, New Testament VI: Galatians, Ephesians, Philippians (Downers Grove: InterVarsity Press, 1998), p. 134.)
Sorry, I do not have a link for this last quote.