Should I pack my drivers licence, Passport in packing boxes ?

Not a good idea. Very difficult to clear customs in Japan without a passport. Illegal in many countries to drive without a drivers licence.

Please avoid unnecessary expense, and wasted time retrieving important items that should not, or were mistakenly packed.

Our advice, nominate a special suitcase or bag where all important items are put, i.e. air tickets, passports, licences that will travel separately as hand baggage..