Nope, that won’t do it. Those screws in the tail cap hold the negative end PCB down and help achieve ground.
The best way I know is to use a clamp meter from the top, after removing the bezel and lens and the cover board then also removing the 4 triple optics, this requires de-soldering the negative lead at the MCPCB and soldering in a loop of wire sufficient to get the clamp meter around it. This will tell you how many amps the LED’s are actually pulling. Remove the loop and solder the black lead back down, replace the optics and the cover board then reassemble the bezel.