a friend at the yard does this so her horse has company on long days at shows and gets the mini out and about they just screwed a tie ring a couple of feet off the ground and somehow managed to secure the breast bar for his tiny height! depends if u have a 1 or 2 horse trailer..
Yes I have done this once before. Just used a bale of hay in front of the mini as a make do breast bar and then horse in other side as usual. I normally would travel seperately but had limited options and it was just a 10 min journey. Seemed to work out fine though.