All instrument panels were finished in butler (satin) nickel and mounted with nickel plated 10-32 screws. A smooth panel with oval shaped speedometer and centrally mounted instrument panel lamp was used through mid 1930. There were four variations of this panel. The earliest, used from the beginning of production through February 1928, had a line marking the edge encircling the instrument panel and the lower mounting holes were not recessed. On the second type, used in the early to mid 1928, the lower mounting holes were not recessed and the rim was clipped above the gas gauge. The third type, used from july 1928 through July 1930, had countersunk lower mounting holes. The fouth type, used alternatively from December 1929 through July 1930 with the Northeast speedometer, did not have a notch for the trip odometer rest knob. From mid 1930 to the end of production the instrument panel was elongated horizontally with a ribbed pattern on the face and a round speedometer. These could be either br*** or steel, finished in butler or bright nickel. Some instrument panels after Arpril 1931 had a distinct line around the ribbed area. The recessed areas above the gas gauge and below the speedometer on the ribbeed panels were painted satin black. The upper mounting screws were 10-32 with a #12 oval (some had a higher dome than normal) head. The shorter answer would've been "No, they are not interchangable".
The Jalopy Journal
