I setup my shipping as fixed for different items.

i.e.
item A - $5 shipping
item B - $8 shipping

I need to add $2 for handling for zone XYZ.
I was thinking of using the 'tax' configuration, but tax are generated from percentage. I already create the zone.
I just want the $2 to be added to customers from zone XYZ.

How do I configure this?