[Identify this Chevy 4-Door Sedan?]

Thanks very much! I will share this with the family.

[Identify this Chevy 4-Door Sedan?]

On Father's Day I started looking through some old snapshots of Dad. He looks duly proud in front of this shiny Chevy. The photo is undated. I can't seem to figure out the data on the car. I'm guessing '37-'40 era? Master Deluxe 4-door Sedan model? Did the 'Sport' model have angled rear pillar and the non-sport a straight rear pillar?

Better picture at: http://www.bradbrock.net/Misc/dadcar42k.jpg