Renaming directories

I'd like to replace the parenthesis with brackets in every album's folder, as follows:

currently: %artist% - %album% (%year%)\%filename%

to: %artist% - %album% '['%year%']'\%filename%

Is this possible? I've been trying to use the convert tool "filename - filename" but I'm stumped. Could anyone help?

Make a new action

Action type: Format value
Formatstring: $replace(%_directory%,'(','[',')',']')

Thanks, dano. Worked perfectly!