Originally Posted by unclearthur
Cantle lift can just as easily be caused by a correct width tree but incorrect panel shape.
And too narrow of a tree can also cause it! My saddles lift at the back to sit balanced, if they're too narrow, and I know to change the gullet plate that way. They lift at the back and, crucially, drop at the front
if they're too wide.
In my case, I know both my saddles fit my horse perfectly panel shape wise, and I can quite easily change the tree with myself with the Wintec easy-change system.
Also - if your horse is not standing properly square with front AND hind legs, the back muscles will not be even, and it may appear that the saddle is not touching one side (usually the dropped side).