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Those are often included with the ebay units to keep the shock travel length the same as stock. You are running OEM style mounts which do not need that spacer. In fact, I am running the ebay specials (UMI wouldn't clear my brake master) without those spacers. The front strut is compressed maybe an inch over what it should be. It looked better and I am not sure if it really matters.
If you want the same strut travel, you'd need to run the spacers under this style mount.
For my front suspension I was considering doing this as it makes sense to regain some strut travel when lowering the car, but decided to follow some advise from someone from FRRAX.com and that it wasn't really needed, I'm guessing it is/was necessary to some depending how low the car is maybe? Raising Upper Strut Mounts - Third Generation F-Body Message Boards