1. What pressure switch did you buy?
2. When you adjusted the pressure gauge, what did you adjust, which way, and by how much? Normally you don't adjust the nut on the small spring. Did you?
3. Are either of the valves partially closed?
Normally you would want the pressure switch closet to the pressure tank. Teeing off where the pressure gauge is, to supply the pressure switch and gauge both, would be good