Install binary rpm package you just built with sudo command:
[tchung@localhost SPECS]$ sudo rpm -Uvh /home/tchung/rpmbuild/RPMS/i386/flash-plugin-6.0.79-fc1.i386.rpm
Preparing...                ########################################### [100%]
   1:flash-plugin           ########################################### [100%]
If you see following error, install compat-libstdc++ by typing 'yum install compat-libstdc++'
then try it again.
error: Failed dependencies:
        compat-libstdc++ >= 7.3-2.96.118 is needed by flash-plugin-6.0.79-fc1