Robert,
Are your records maintained in a hand written index AND a computer index?  Since 1984 the Clerk and Recorder has keyed information into a computer system in my county. 
Hand posting was stopped.  We only have the computer index to search back to 1984, then run the books further back if the records go back that far.  The plat room stll hand posts anything that changes ownership, but the C/R only keyes the recorded documents.  Wondering if your counties maintain both types of indexing systems.   Thanks,
Kim