Take the Solar top from your garden stake and glue the metal ring portion from the top of the mason jar to it. You will not use the center pressure lid, or the bottom portion of the solar lamp. Save these parts for another project.
Place the solar top upside down, run a bead of glue around the outer edge and lay the metal twist lid (open in the center) onto the solar light. It should fit perfectly, hence why I used the wide mouth jar.
Try fitting them together in a dry run first just to get the hang of it.
Once it is glued place a heavy object on top to hold in place until it is dry ...usually a few hours.