Disassemble the control switch covers. Remove the hand grip. Loosen the brake cable. Loosen the bolt. Disconnect the brake cable from the lever. Install the brake light switch. Loosen the bolt from the new brake lever. Mount the brake lever on the handlebar. Mount the brake cable in the lever. Connect the brake light switch. Fit the bolt and the bush in the brake lever. Mount the control switch covers. Fit the hand grip. Mount the brake cable on the rear side.