Here's a link to a photo. It's a 3-speed, top left shift position is reverse. I found some additional info on the VCCA site that these were leftover 1933-36 Chevy transmissions used after the war in 1946.

1946 Chevy Transmission


1959 Chevrolet 3800 Pickup
1937 Chevrolet GC Panel
Can you still call it a barn find if it's your barn?