This is the inner spring that breaks in half under the lever inner arm. $16 shipped in the USA. I bought 2 needing only one.
http://cgi.ebay.com/ebaymotors/1948-1951-CADILLAC-GEAR-SHIFT-LEVER-TENSION-SPRING-NOS_W0QQitemZ290225989821QQihZ019QQcategoryZ42606QQssPageNameZWDVWQQrdZ1QQcmdZViewItem