If you slapd restart it will fail to start. To correct the configuration you need to start slapd. To start slapd you need correct configuration. It is the end of your efforts.
I would advise you to use the proper tools if you get into such a situation. Like slapcat and slapadd (for offline export/import). OpenLDAP 2.5 will also have offline modify (slapmodify).
--Quanah -- Quanah Gibson-Mount Server Architect Zimbra, Inc. -------------------- Zimbra :: the leader in open source messaging and collaboration