When you refer to "control box" you must be talking about the pressure switch since you are talking about a 2-wire pump.
Setting the pressure switch is probably the easiest part of the problem.
There is usually a nut that is identified as "Turn clockwise to increase both start and stop settings"; and another one that is identified to increase only the stop or shutoff setting.
I am going to assume that the 30 psi tank air pressure is ok, and describe how you can set the switch to operate from 33 psi start pressure and set your STOP pressure.
Procedure:
1. Drain the tank with the circuit breaker off.
2. Turn on the pump and observe the pressure when it first builds up pressure. It should equal the air pressure in the tank (30 psi?). Let the pump run until you have 35 to 40 psi in the tank (at least 5 psi above the initial point). Turn off the breaker and drain the tank until the tank gauge is about 3 psi above the initial "empty" air pressure.
3. Now the pressure switch is probably ON because you turned off the breaker when pressure reached a few psi above the initial tank pressure. Using as flat bladed screwdriver, lift up on the end of the pressure plate that is at the base of the switch with the end near the adjusting screws until the switch clicks to the OFF position.
4. If the switch immediately clicks to the ON position when you take away the screwdriver, then turn the screw/nut counterclockwise to DECREASE the pressure setting and repeat Step 3. If it doesn't immediately click to the ON position, then adjust the main screw until it clicks ON. You are going to adjust the screw until the switch transfers from the OFF to the ON condition at about 33 psi.
5. Now run the pump while watching the pressure gauge. When the pump gets to the pressure you want for a STOP pressure, or a little above, turn off the breaker.
6. Now adjust the screw identified for "Stop pressure only" until the switch transfers from "on" to "off" at the desired pressure.
7. Run the pump to see if the settings are OK and tweak as required.
If you upgraded the pump without changing the tank, then the pressure tank may or may not be adequate.
