The aircraft had been flown from an adjoining property by the owner. Because of difficulties encountered in starting the engine, the owner left it running while the pilot for this flight took his seat. At the time, weather conditions were hot, with a shade temperature of 46 degrees Celsius, and with little wind. The pilot subsequently advised that during the take-off roll he looked for the airspeed indicator, but was unable to locate it on the instrument panel. After lift-off a steeper than normal nose-high attitude was adopted, and the aircraft stalled from a height of about 20 feet above the ground. The particular aircraft was an early model of the type, with a different instrument panel layout, instrument coaming shape and height to that which the pilot had been operating during the preceding month. The pilot believed that the attitude selected after lift-off was the appropriate one, but because of the difference in instrument coaming heights the actual attitude was too steep. The departure had been hurried and the pilot had not familiarised himself with the layout of the instrument panel. The extreme ambient temperature had probably caused a degradation in the pilot's performance.