I apologize if this isn't as helpful as providing you with a part number for your back up lens, however I think it's valuable enough info...

Here is a picture of one of the two back up lenses I pulled from an '85 Euro 300TD not long ago (along with the rear bumper). The lens looks just like the replacement you purchased from Pelican.



So perhaps the issue is that someone replaced the back up lights on your wagon with a different variety? Therefore a part number for what should be on a 300TD might not be super helpful to you.

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1979 300D 040 Black on Black - 1985 300D Maaco job (sadly sprayed over 199 Black Pearl Metallic) on Palamino

http://i.imgur.com/LslW733.jpg

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