Upgradeing already customised weapons.

Is it possible to change the upgrades in already customised weapon? I'd like to know that before customising my pretty bows

Customizing a weapon at a weapon crafter in town for 10 gold adds 20% damage. In return, you can no longer use the weapon for any other character, i.e. it is eternally tied to you.

Upgrading a weapon by means of a mod adds some feature, e.g. a different damage type (ebon/fiery etc.) or another benefit (e.g. fortitude - extra health/defense - extra armor). Each weapon suitable for upgrading exhibits two upgrade slots. These can be upgraded over and over, regardless of weapon customization. However, please remember that a weapon mod effectively replaces the existing upgrade in the particular slot.

Customizing has in no way any effect on MODS on the weapons, it just means you can't use it on anyone else or sell it <for useage> to others PCS

--The Shim

Uh, that's all I wanted to know, You wouldn't have to explain me the rest . Big thanks fot the answer anyway.