To exchange a symbol instance’s definition with another:
Select the existing symbol.
In the Object Info palette, click the Replace button.
Alternatively, right-click (Windows) or Ctrl-click (Mac) on a symbol, and select Replace from the context menu.
The Choose a Symbol dialog box opens.
Select the replacement symbol from the list of symbols available in the current document.
Select Replace Class to replace the symbol’s class with the class assigned to the new symbol’s definition, or deselect it to retain the class of the replaced symbol.
Click OK.
The old symbol instance is replaced with the new symbol instance.
The new symbol uses the settings from the replaced symbol. Future occurrences of the new symbol are unaffected by these settings.
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