Our run was 7 feet wide so we cut the PVC to 7 1/2 feet. Eight feet made it seem too high since the run was already six feet tall and would require more hardware cloth. Here is how we worked each section:
Attached the end section by first attaching it to the rail of the kennel, then the last PVC pipe, then trimming the extra.
Hope this helps.
Gail

Attached the end section by first attaching it to the rail of the kennel, then the last PVC pipe, then trimming the extra.

Hope this helps.
Gail