34079 looks too dark to me. The ones I remember were lighter and brighter--not quite 34151 Interior Green but not that far from it.Testors FS 34079 Dark Green
Was typing this:
I'm under the impression that MOST of the M16s used in Vietnam were A1s with the forward assists. USAF stayed with "straight" M16s and none EVER had a forward assist, though they did adopt the birdcage flash hiders and mag-button fences.