Hi Lawrence
I am not sure that reducing the Assignment Units against each resource is the right way to do it as if a task is scheduled to a given amount of time then more resource should be added in order to achieve it in less time. However if you really want to do it the way you suggest then follow these steps:
1. Select Task Usage View.
2. Insert two new columns to the view:
- Overallocated
- Assignment Units
3. Filter the Overallocated column to "Yes".
4. Then change the assignment units for each resource until the Overallocated column reads "No".
Hope this helps.
Good luck.
Tony