Here are the color names for all Reatta interior colors:

• White (1990-1991 convertibles)
  • There will be a standard GM white in the S-E-M color book for 1990.
• Sapphire Blue (1988-1991)
• Medium Beechwood (1988-1991)
  
  • On Reattas, this color is called "saddle", but the Medium Beechwood is actually the correct corporate color name.
• Medium Dark Gray (1988-1989 only)
• Light Slate Gray (1990-1991 only)
• Garnet Red (1988-1990 only)
• Flame Red (1990-1991)
  
  • 1990 as a trim color on select-sixty convertibles
  • 1991 for complete interiors.
  • Dash tops on 1991 models with this color interior will be Satin Black.

More information about colors and color codes can be found here.