If you dealing with these kinds of jobs you either get a generic stencil and use a kapton tape as a mask or you invest in a laser cutter capable of cutting stencils in a half/quarter of a mil stainless sheet.

Also RoHS goes out of the window and you use a leaded tin which makes your life so much easier, as well as usually guarantees a longer life time for the fix because it’s far more ductile after soldering.