The late Master Mike Wollmershauser was the head of the American Hapkido Association and 8th degree black belt under Dojunim Choi Yong-Sool. Master Mike was the only non-asian to study with dojunim Choi, Yong-Sool.
This is his VHS Video tape No. 3 - yellow to blue belt from 1984:
Unfortunately, the quality of the recording is no longer good. The VHS Video casette was in my basement for over 30 years. Unfortunately, this caused damage to the magnetic tape.