Thank you yichusdik.
I had a chance to check online and found out that hebrewbooks.org has the first 9 volumes for d-load. I used my above mentioned sefer (compiled & written by R’ Avraham Meir Weiss, published Bnei Brak, 5769) as well as Shem HaGedolim by the Chid”a (we have a tradition that I am a descendant of the Chid”a) in my genealogical work. Sefer Yochasin is useful for pre-Geonic lineage. Sometimes little fragments of yichus/history are found in other seforim, not necessarily biographical. Hatzlacha Rabba with your research.