So to clarify - my hot side temp is 88f, my cold side is 80f. The ambient is 80f also. Placing the temp probe under the substrate next to the glass, the temp is 95f max.
These temps now seem good and safe for a Ball Python ?
Originally I had 3 inches of substrate ! But I think the root problem is the tank and size/shape of tank. It is square so it is difficult to encourage a temp gradient in there. Using the bubblewrap around the outside glass has helped insulate and trap some of the heat rather than it rising out of the mesh lid.