Conversation so far:
what happened to zz top in 1969?
They released their first single, "Salt Lick", in 1969.
who started zz top?
CANNOTANSWER.
who were the members?
The original line-up was formed in Houston and consisted of Gibbons, organist Lanier Greig (died February 2013) and drummer Dan Mitchell.

Question: who was a leader?
Self-contained rewrite: who was ZZ Top's leader?