I have a friend that has three hie ties on her
gooseneck. One is on the passenger side near the back, one is on the
driver’s side near the back so those two horses can see each other and
one is on the driver’s side (no doors on this side of her trailer) far
enough up that the two horses on that side could never touch each other and
obviously can see one another as well. We traveled with three horses for
two years with her system and it worked great.
My trailer has two hie ties on opposite sides near the back
so the horses can see each other. I think it does help if they can see
their buddy.
I had my hie ties installed by the local welding shop.
They installed extra support bars between the support beams of the trailer and
mounted the hie ties to those bars. It is a nice clean mount and very
sturdy.