I have a 94 z28 vert and the top is sagging and ballooning badly. I took it to a local shop and they mentioned that the center strap that runs between the sides have come apart from the top, causing the ballooning. I need to know, if I order a replacement TOP PIECE ONLY, does it include that center strap? Also, it looks like all the other parts, back glass, pads, etc. are in good condition, but are any necessary for the install? I'll probably go to a professional shop for the installation, since I also heard something about modifying the top bow on 94 models. Can anyone add to the "top bow mod"? Thanks for any and all responses.

Here's a link to the top I'm considering:

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