Definitely aftermarket stuff....
Unless this is a Collector Edition, the rear glass doesn't open. If it is a Collector, then I would suggest removing the louvers... the hinges for that glass are flimsy to start with, and I would expect any additional weight to add to the already overweighted glass, and the attachment. They're prolly not that heavy, depending on what they are made of...steel, or aluminuminum...

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Joel Adams
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