My original/untouched '70 Satellite 383 4-bbl A/T car had a turquoise motor & AVS carb. The orange vs. turquoise '70 383 4-bbl deal has been debated here before, and IIRC the orange ones are an anomaly. As previously stated, orange 383s & 440s would signal RR/GTX. '69 RR 383s with A/C were turquoise 330-horse motors, not the 335, had one. Possibly this changed for '70, but not on mine. All the cars I'm referring to were St.Louis built.
The actual blue color came later with the low-compression "smog" motors.