Traditionally my family knew we descended from a certain gadol but didn’t know how.
For the project my sister was researching this gadol and at the end of one story she read the magazine said that the author is an eight generation descendant of this gadol.
After contacting the author she determined that he is my grandmothers third cousin but he had a tree from his great-great-grandparents down which included my grandmothers grandfather. He then offered a tree going up to Rashi. From there my father did research and traced it to Dovid Hamelech and eventually up to Odom.
If the information is there- it’s there. If it’s not there I have no idea how to go about getting it. Sorry 🙁