How long should the new elastic straps be that are between the second and third bow on the 350z convertible top. I just got a new top that came with long straps that I need to modify for length.

 

I did my top a few years back and straps were correct length. A wild guess would be measure distance between bows and subtract 1/3 for adequate tension. If you're cutting off the eyelets you might put a tiny washer under the rivet head.
Gl!