Imagine flying direct track Sydney to Essendon. IAS 85 knots. 7000 ft. Fully IMC. Iced up. Moderate to severe turbulence over the ranges. Wind at 5000 ft 220-270 at 60 knots. Drift angle between 35 and 55 degrees. Thunderstorms with hail and snow. No ground based radio navigation aids en-route or anywhere at all. Flight instruments one ASI, one altimeter, one Turn and bank indicator gyro driven from a Venturi tube . No pitot heating. No anti-icing. No artificial horizon. No directional gyro. One magnetic compass. An inclinometer which is basically a vertical spirit level that gives you an indication of nose up or nose down or nose level. You can't any more Limited Panel flying than that.
Could have been a description of an IFR 402 I flew in the early 70's