I was planning on pulling 160 feet each time with 2 pull boxes and using a forklift as a tugger with rope rated for 9000 pounds plus
I forgot about this part. There is ABSOLUTELY no need for pull boxes. Who cares how long the longest snake is. Suck a jet line in with a vacuum and balloon, then pull in a light rope or mule tape, then use that to pull in the pulling rope.
Sometimes I feel like if I answer any more questions it is like someone trying to climb over a fence to jump off a bridge and me giving them a boost.
Answers based on the 2008 & 2011 NEC. If you're on the '14 already I feel sorry for you.