You need to put the 45° mirror on to see the bottom of the big guide (chin guide).

The big guide was the first to go on the two I rebuilt.

Did you take pictures? Even from the side you may see "new". The plastic clips do come around the metal a bit, also the aluminum base will look as lot different so that could likely confirm if it's original

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)