Ok, what I'm seeing is in the pic below. Looking at where the logs are in relation to the bunks that isn't going to move at all. So when the truck makes a turn and lets say it turns sharper than the image shows and the tail of the truck arcs out farther say the truck turns to a 90 degree angle to the trailer, the front of that trailer as shown in the video up top has to give to allow for the truck to turn or it would pull the trailer apart.... The part of the trailer (Number 14) won't give as on a real truck it would be welded solid.... So where (number 17) would be the give point that would go in and out to allow the truck and trailer to make a turn. It may only move in and out about a foot or less but it has to have some give...
Anthony, I haven't built any kit Peerless trailers yet so I couldn't tell ya on that. I did find this pic and it is pulled out a lot farther than it should be but it gives the idea.... click the link, pic won't load up...
https://www.google.com/search?q=peerless+logging+trailer+model+kit&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiMsvDi1MHVAhUd3YMKHYZ_Dj8Q_AUICygC&biw=1680&bih=941#imgrc=VJr-noaO3-3yZM: