Modify Workstation Assets

Can anyone offer advice on the following scenario?

Yesterday
Workstation Name      |      Service Tag
AAAA                              1111
BBBB                              2222

Today after Service Tag 1111 died
AAAA                              2222 (swapped HD 1111 into this system)
BBBB                              1111 (disposed)

How do I clean up my Asset list/properly show what has been done? System is confused when performing asset scans now. I hope to repair system 1111next week and redeploy, but would like to keep all history if possible.

FAILURE :Database exception while updating Workstation. : Duplicate entry for key

Please report the problem to the system administrator, with the Error Code - 1,280,511,727,366.