Can' t find GamePiece coding tutorial

IN VASSAL Reference Manual

it mentions
For highly specialized pieces, you may supply your own custom Java classes. The Java class must implement the GamePiece interface and most commonly extends the Decorator class. First, add the Java .class file to the module file using a Zip utility (remember to preserve the package structure: e.g. the class should go in a subdirectory within the Zip that is named for its package). Then hit the “Import” button and enter the fully-qualified name of the class (if the package name is “PathsOfGlory” and the class name is “CustomPieceMover” then enter “PathsOfGlory.CustomPieceMover”). The Trait corresponding to your class will appear in the list of available Traits and you may add it normally. See the Coding Tutorial for more details. I can not find the coding tutorial for this.

Can Someone please direct me to its location. Sorry for the Gruff tone.

One of these might be what you’re looking for:

Thank You. I have read it it before and forgot all about it. Old age sneeks up on you.