How to Deactivate an Employee whom "user person type" data has changed

Content

Hi,

We only manage "Salary" users in the system, and recently one of them was changed to "Hourly".
This user is still having the same access and appears in all modules as if he were Salary.
What can we do to deactivate him?
we need to keep his information like performance goals, people development information, performance rating, etc, etc, from the previous years.

Thanks in advance