i did a dry fit on mine before powder coat. then when it was all painted it was just a simple final assembly. your doing a great job and my inner fender did crush a bit too. it was only about 3/16" but it did move.
True I'm doing this a little differently than most by powdercoating first. It just made sense after taking with you to go ahead and try it in one shot so the mock up is the same step as install. Just seems like it's going slower than it should.