SG Columbia IS-4 Premiere Version 1982, Prototyp ?

This is a car i het ready today, it is a very early SG Columbia IS-4 from 1982. Maybe this one is an Prototyp? many parts are a bit diffrent to the normal IS-4. I built a new IS-4 some days ago so i can see very good the diffrence to this car. All alloy parts are black caoted, the rear driveshafts are thicker, the pins of the suspension are 4mm and many other small diffrences. This car is a slightly used one so there are some scratches on the bottom. I build this car with a Cipolla Master because i think the gold head looks very good to the brown epoxy plates. The rc in the car are Robbe RS60 servos which are period. There last pic shows the second of my IS-4, i will show it later.