Looking at the four pillar forms. I have been told the GJFF is the oldest.
the iron wire was added later and WFH composed the tiger crane.
I have read somewhere (maybe on this forum) that the older hung sets could be practiced on the space of four tiles,(from what I guess a stone floor tile would be about 2 1/2 to 3 ft square give or take)
also long arm was added during WFH's time,
So if we took GJFF and 5 animal, removed the long arm techniques and narrowed and raised the stances maybe that may look like the the "oldest" hung
maybe , maybe not