This is great news for Tektronix collectors and restorers. We have worked with Tektronix to obtain a release for the Master Publication Index (MPI). Our MPI is from 1986. It is available on Tekwiki at Reference Material (external site).
The MPI is an index by product or option that indicates what printed material was associated with it and the part number. This extract from the MPI for the 7704A indicates there was an Owner's Manual, a Service Manual, and information for various options included in the Service Manual.