I am not clear to where you mean. A "skeg" is a fin or unmovable part of the keel. The extention of the keel where the rudder shaft enters the hull is call the princess fairing. The straight drop down the keel where the leading edge of the rudder meets the keel is the rudder fairing. These are terms passed down in our history.
The rudder is supported by the shaft as it passes into the hull and secured as shown on the building site. Some have placed a strut over this shaft and glued it to the hull. This shaft also extends down into the rudder about 60% and angles aft at 60-45 degrees. This stabilizes the rudder and prevents slippage.
Older boats do not have the half round fairing that envelopes the leading edge of the rudder. This can be made and has on many older boats till builders worked this into the hull mold. I have never seen a supporting hinge for the rudder on the EC12.