Hey Chris,
Fortunately I've used DDP's consistently over the last few years so I understand how grid index features works. I tried using the strip map index and it appears they are still using a one spatial reference for all. I want to get away from doing anything manually, as there are hundreds of lines I would have to sort through. Is there any arcpy scripts you know of? I've looked around EVERYWHERE and can't seem to find anything.
Essentially what I'm going for is a map book with hundreds of lines and the DDP's show these lines at all different spacial distances with the map fitting he best way possible. For instance, the map book is positioned horizontally. With a line drawn north/south, I would want the page to position vertically so you can see the line much more clearly. These lines can span anywhere from a block to 8 blocks.
Thanks for the help!