i cleaned out my 2008 imac OSX 10.5 with the start up disc. how do i install the 10.5.8 system ?
If I have understood you correctly, you will have to reinstall 10.5. Then you can update (free) to 10.5.8 via Apple Software updates or the Combo updater below.
Mac OS X 10.5.8 Combo Update
Retrieving data ...