Patrick,
1938-1947 is one part number. And, 48-53 is a different part number.
This may have to do with the engine bolts and/or the transmission bolts (or, maybe even another difference).
Wait to hear from someone who knows. There is no question that you cannot use a 1954 and newer clutch housing, because the rear motor mount changed in 1954.
What year 3-speed transmission do you have?
