The way you check droop with the TC4 (and the way they are indicated by the setup sheets is the following)
You must use the associated droop gauge.
1.Use the flat part next to the step increments with the numbers on the gauge and set i against the bottom of the chassis.
2.The step increments must be facing towards the outside of the arm, rest the outside part of the a arm (near the hinge pin) on the number desired.
3.Turn the set screw adjustment to make sure that the arm comes down exactly to the point of contact with the droop gauge.