Answer:
The Trash Can should be a permanent feature, like the Finder icon at the other end, on the Dock. You can dig down to:
/System/Library/CoreServices/Dock.app/Contents/MacOS/Dock
and hack the Trash settings to give you a Remove from Dock option when you click and hold on the icon, like any other application, but this will break the Code Signing and will be reset when the computer is restarted again restoring the Trash Can to its rightful place.
It is not clear what is trying to be achieved but would a Simple Finder set up help? (See links below)