replacing mods

i was windering if u can replace a mod that u put on a weapon. i know that u can change the mod that u find the weapon with.

if you want to change you overwrite the old mod by applying the new one

All weapons may be modified over and over, with the exception of Green items, these items cannot be modified. You cannot remove a modification from a item (weapon or armor) without destroying the item, and certain bonuses / negatives are inherent to the item, such as +15% dmg when your health is > than 50% of your maximum, and cannot be removed or changed.