I'm going to guess that 4G54 is the same as G54B or was that a mistake. Anyways, I pulled it of a 1987 Mitsubishi Mighty Max. Here is a picture that I took of the vehicle safety certification label:

IMG_20160528_103558.jpg

According to the VIN number breakdown:

Country: Manufactured in Japan
Make: Mitsubishi
Vehicle Type: Truck
Restraint System: 4001-5001 LBS.
Car Line: Truck 2WD (PRE-1987)
Series: Low
Body (Mitsubishi): ?
Engine: 2.0 G63B
Model Year: 1987
Plant: Nagoya-2
Transmission: ?