Unfortunately I don't have pictures of the saddle on the horse, but I have a saddle pad picture that is very confusing as well as my personal experience.
Saddle pad, unwashed and used 4 or 5 times. Please note it's not laying flat because the pad has built in wither relief.
When I look at the sweatmarks after a ride, it appears as if there is a large dry spot near the front of the panel. But sometimes, the dry spot is on the front and back. Sometimes it spans the whole panel except for the outside edges. The gullet seemed to fit well...But now I'm not so sure?
My main concern is that he always gets upset during saddling. No matter the saddle or the fit he always takes a few steps forward and back (I think it puts the saddle in the right place for him. Sometimes I could put it on very precisely and he would move less.), but now he's starting to get a little more upset every time I saddle him. I don't think he has a sore back, he doesn't react when I poke or prod and barely flicks an ear when I (accidentally) sit down too hard.
Anyway, what do you think? Can I fix it with shims? Should I be fine for now? Thanks everyone!