Well I just think he would have pistons originating from an A10 engine.We didn't get anything GX here,so I had no knowledge of these engines having the two types of pistons.Due to taxes and high fuel price (even then) the A10 engine was very common and easy to find here,and the swap in A12 engines has been known since the early seventies.I thought that since the car had a special gearbox and LSD,there might have been a full spec engine in it with the 76.8mm pistons to bring the engine to 1298cc.Seems DatsunSSS wasn't that lucky.....