How can I tighten a brake handle bracket holding the handle of brake handle housing?

SOURCE: the housing of my brakes on the handle bars is

for gmc denali bike 1-disconnect brake cable from caliper 2-squeeze brake handle all the way till it touches handlebar 3-shine flashlight in in opening at top of hand lever 4- locate allen screw 5- loosen allen screw 6-remove handlebar tape and slide handbrake assembly off handlebar.