I do remember that this was discussed a few years ago on this forum, before I bought the ones I have. Someone claimed they did just that.
I saw a Freewheeler not long after that with the Tri Glide bras on it, they were saggy on the top part of the fender where it dips down to the bob tail. I would not have been happy with them on my trike.
Thanks Lola, I was looking at that fender dip and thought it would be a problem area.