1. Droid PositionTularan Marsh, Northeastern part, above a small ceiling crack.
2. Droid PositionTransport Station 5, North From Tularan Marsh, at south side on the first floor of a huge structure.
3. Droid PositionThe Sinking City, above the engine of a crashed spaceship.
4. Droid PositionThe Sinking City, from Collapsed Medical District you can notice this Droid standing high in the air, at the top of the destroyed building structure.
5. Droid PositionRepublic Resettlement Zone, Northeastern part, at the floor edge, in the air.
6. Droid PositionRepublic Resettlement Zone, Southwestern part, high in the air, at the floor edge.
Source: Official MCR-99 droid locations (hidden planetary achievements), MCR-99 Droid Locations post 2.0 on Swtor official Forums. We would like to thank SWTOR community members for all additional information.