From what we know
Early Nieuports had early wings, not reinforced, without mini ribs, that were attached to a leading edge of the both wings
also, early Nieuport`s had a square shape maintenance hatch on the fuselage starboard side
Should I also mention, that there was no oil tank on the firewall, that we all got used to, as it was installed in the cockpit, next to a fuel tank, and had an odd shape, due to fuselage rigging.
Most of the early types had a transparent wing cut out, covered by cellulose