The P-166C was developed at the request of the Australian agent Forrester Stephen for a 13-seat version for commuter airlines. This was achieved by moving the undercarriage to fairings on the fuselage sides, freeing up cabin space. The P-166C also had more powerful engines to lift the heavier load. Only two were built and VH-FSC was the only one to reach Australia. It failed to win orders.
VH-SPF was first registered in December 1967, ex N3938D. It did come on the British South Pacific colonial register as VP-PAN and the Papua New Guinea register as P2-SPF. It returned to Australia as the end of 1975 remained current in 2018 despite accident and storm damage over the years.