Back then there was a recall on the accelerator pump cup and I think the replacement green or orange IIRC. Found this online.
Chrysler Motors Corp.
NHTSA ID No.: 77V-242
Date of Company Notification: 12-23-77
Model: Valiant, Volare
Model: Aspen, Dart
Model Year: 1975, 1976, 1977
Number of Vehicles: 1,300,000
Carburetor accelerator pump seal distortion caused by contact with certain type gasoline may result in persistent hesitation or stalling. Also, premature actuation of exhaust gas recirculation (EGR) system may result in persistent cold engine hesitation or stalling. (Correct by replacing pump seal and EGR system retrofit modification.)