If you want the new cost codes to show as original estimates, I would use Enter Estimates again. Enter a negative into the old cost code and then enter positives into the new cost codes. They will all show in the original estimates column in the job cost report.

You can go to JC > Tasks > Enter Estimates and using the original date of the prior entry, enter a negative amount to the existing cost code and enter positive amounts to the desire re-allocation of the estimate.

Art MInds
Senior Independent Consultant