Bobby Darin's "Rock Island Line" and "Silly Willy"

To-day, I listened to a compilation album of Bobby Darin titled Purely... Bobby Darin.  In the continuing theme of train-sounds-in-songs, I've noticed that in his version of "Rock Island Line," he sings some "ooh"s, ostensibly to mimic the train's whistle.

Also, I think I've found a connection to Cab Calloway's "Minnie the Moocher" in "Silly Willy," which is also included in this collection.  In "Silly Willy" there are the lines:

Willy was a-dreamin' 'bout an automobile
With a pair of diamond headlights and a gold steering wheel

They're not exactly the same, but they do bear some resemblance to lines in "Minnie the Moocher":

He gave her a home built of gold and steel
A diamond car with the platinum wheels

Both mention cars, diamond, and gold.