Change value in Condition Type in Sales Order.

Hi:

We have a question related Standard Sales Orders / Quotation. In our system, we have defined a Z Condition Type at item level.

We create Sales Order with reference to Quotation. The problem we have is the next:

Sometimes we need to change manually the value of this Condition Type in Sales order but always take the value of original quotation for this condition.

Please, do you know how  we can change the condition type manual with no change original quotation?

I have looking for in

Logistics Execution / Shipping /  Basic functions / Pricing / Define condition Types

but I find no solution.

Thanks in advance for your help.