I have 2 Stilo MWs; one built in March 2003, the other built in November 2003. The March one has 3 screws, the November one, 2 screws and a peg. The change point must have been sometime between the 2.
You can see from your battery box which one you have. Early battery box has 3 captive nuts. Later one has 2 captive nuts and a peg that fits into a cutout in the cover.
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