Best way to adjust the tongue weight on my trailer?

Tow the trailer with Bronco to a truck scale. Position the rig so only the trailer is on the scale. After getting just the trailer wheel load, crank down the tongue jack until it just lifts off the ball. This will give you the total trailer load. Total trailer - trailer wheel = tongue load. If the tongue load is too high, crank up the tongue jack and move the Bronco back until you get the additional load on the wheels you need.