Ron - According to a 1929-39 Chevrolet Master Parts List, the 1936-39 Chevys used the same flexible hose assembly for both front wheel cylinders and at the rear frame to axle connections. GM# 476719 is the listed part number. There are many of our usual vendors that offer a reproduction hose (with the correct ends and length) to replace the originals. All I found show them using 1/8" ID hydraulic flex tubing in their reproduction pieces. I agree with JoeH that the tubing inner diameter shouldn't be an issue as the flex lines should allow for sufficient volume to operate the wheel cylinders.
Others with more fluid dynamics knowledge should be along to offer more insight.
