side scoop confusion

[samborskij]

I have been looking at a number of used 2004 Medium Spiral Gray Vette and noticed a difference in the side scoop, some have a straight bar running laterally in the center of the scoop. All of them have a "4" in the proper place on the VIN.

Can anyone explain the difference to me ?

 

[njlouc]

Just a guess here, but the straight bar you are looking at was a factory option ~$75.
SO not all cars will have them. The purpose was to protect the door in the parking lots.
They also added an element of "style". Some people like / some hate. AFAIK they were available for the full run of the C5.

Update: look in the glove box door and you will find all the build codes. B84 = body side moldings