Yes, I remember those days, just a young whipper-snapper then. But my family talked about it for years. How the did the WTS build up excitement ? See 1941 then the frequent use of this (6,000 years of human human history, until 1955, mention of 1976 end of human history, to 1966 then 1968 solidifying 1975 teaching)
In 1941, the WTS said this:
Watchtower 1941 September 15 p.288
"Receiving the gift, the marching children clasped it to them, not a toy or plaything for idle pleasure, but the Lord’s provided instrument for most effective work in the remaining months before Armageddon"
https://www.jwfacts.com/watchtower/quotes/end-soon.php
Then in 1955, the WTS said this all the while emphasizing that 6,000 years of human history had almost run out:
https://wol.jw.org/en/wol/d/r1/lp-e/1955089?q=6%2C000+years&p=sen
1955
According to Genesis 1:24-31 Adam was created during the last part of the sixth creative-day
period of 7,000 years. Almost all independent chronologists assume incorrectly
that, as soon as Adam was created, then began Jehovah’s seventh
seven-thousand-year period of the creative week. Such then figure that from
Adam’s creation, now thought to be the fall of 4025 B.C., why, six thousand
years of God’s rest day would be ending in the fall of 1976. However, from our
present chronology (which is admitted imperfect) at best the fall of the year
1976 would be the end of 6,000 years of human
history for mankind, 6,000 years of man’s
existence on the earth, not 6,000 years of Jehovah’s
seventh seven-thousand-year period. Why not? Because Adam lived some time after
his creation in the latter part of Jehovah’s sixth creative period, before the
seventh period, Jehovah’s sabbath, began…
It was not until after Adam completed this assignment of work
that his helpmate Eve was created. Since God created nothing new whatever on
the seventh day, Eve must have been created on the sixth day; and this the
divine record confirms in its account of the sixth day: “God proceeded to
create the man in his image, in God’s image he created him; male and female he
created them.”—Gen. 1:27, NW.
The very fact that, as part of Jehovah’s secret, no one today is
able to find out how much time Adam and later Eve lived during the closing days
of the sixth creative period, so no one can now determine when six thousand
years of Jehovah’s present rest day come to an end.
--But the WTS came up with
a workaround this in 1968:
Since
it was also Jehovah‟s purpose for man to multiply and fill the earth, it is
logical that he would create Eve soon after Adam, perhaps just a few weeks or
months later in the same year, 4026 B.C.E. After her creation, God‟s rest
day, the seventh period, immediately followed. (The Watchtower May 1, 1968, p.
271);
“A great thread by Terry Wahlstrom can be found
at this link)
https://www.jehovahs-witness.com/topic/127651/creation-eve-interval-affecting-1975