Great thread. I can tell you that by 1970 may dad already had 510 cards from the set. He was 30 years old that year and used to buy T206's in lots. Bought his first Wagner in '72 and another in '74. Not sure what year he actually "completed" the set but it was during that period. He had at least one variation of every card, including the Magee error and several other oddities.
At the bottom is his bio from "Who's Who in Card Collecting" from 1970:
