I wanted the T-Rex to be able to stand on its own feet without supports, and also give it a more realistic stance.
Most of the changes I could do by bending the printed parts in hot water and hotglueing them slightly different.
There was one part (femur of right leg) that I could not "correct" with these previous ways, so some STL modification was needed. I used blender for this.
Disclaimer: my blender modeling skills are not so great, so this model is purely functional and needs hotglue to attach it to the rest of the skeleton.