There is an adjuster on the handbrake itself, however if it's adjusted too much the shoes in the drums never go fully back leading to other problems.
There should be a self-balancing bar for the handbrake cables, so they would need to be miles out from the handbrake not to be balanced.
The correct procedure is to back off the handbrake lever adjustment so the shoes go fully back, then adjust in the drums until the brakes are just fully off, then adjust the lever back up to be correct. Bearing in mind the shoes settle after changing, I would advise following this procedure.
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