The astronaut figure was based on Revell's previously released Gemini Astronaut, and did not have correct detail.
The model was marketed by Revell just after STS 51-A, where Bruce McCandless became the first to fly the MMU during that Shuttle flight.
Unfortunately, they did not do sufficient re-tooling to the astronaut figure to differentiate it from the old Gemini Astronaut state.
I had to scratch-build the front control box and seamline between the Hard-Upper Torso (HUT) and Lower Torso of the Shuttle sapce suit, or Extravehicular Mobility Unit (EMU).
These were fabricated and blended into the suit. The same is true for helmet work lights and visor details.