See photo for item bolted forward of differential banjo. Overdrive?, Under-drive?, or? Lever on passenger side has hole in lower portion for clevis pin that connects to linkage with a shift knob that comes up through the rear portion of the floorboard - much like a Mitchell OD shifter, but further back. It's on a '29 A stored since 1965 (with 4 Goodyear Airwheels and hubcaps).