Please let me know if we can install 6.4.8 Service Pack in a instance which already has 6.4.7 SP installed. I tried to install with force upload option, since SP is cumulative pack of previous fixes, i thought it will work, But my instance is still pointing to 6.4.7 under "/system/console/productinfo".
Please let me know if it needs to be installed only with 6.4.0 instance.
Yes, it can be installed. If product info is not showing the right value, most probably this means the service pack installation didn't happen properly. Once successfully installed, it show the below log lines in error.log