Can't be sure with the 166, but the 147 is not a scrubber. In fact the tyres all around seem to wear very even. Normally what you describe would indicate the tracking, toe-in/out needs adjusting, but camber could be another consideration, and bush play/wear? Castor would normally give you an indication on the steering wheel . Think those latter two, camber, castor, are pre-set on a 166, as are most models?
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