What am I looking to adjust on the rear drums or handbrake cable when one side locks hard on two clicks but the other side only locks hard between 3 and 4 clicks? On two clicks it is fairly easy to rotate the drum by hand. I've had both sides clicking on pressing the brake pedal after managing to blindly unhook the adjuster thing in both drums but it continues to be out of balance on one side.

MOT failure code was 3.7.A.9 and after playing with the brakes found one side was looser than the other resulting in the poor braking efficiency on the RBT.

 

I'm not sure what you're asking? Wind the adjusted around (Lengthening) on the 'looser' side if that helps.