MAy 15 1975.
 

According to this article, on that day Fleetwood Mac launched their first tour with Lindsey Buckingham & Stevie Nicks.

Any ledgie went to a show that year?

https://www.wxhc.com/on-this-day-may...-stevie-nicks/

Haha, they mention the two ringers. Mike and Neil.
That is certainly a part of the B/N history.

And no mention of Rick & Billy, who are more involved in the band history, for obvious reasons. Well I know the article is not about the band history, but if we talk about Lindsey's replacements, I feel more happy mentioning R&B.

This would have been a spectacular time to see the band, this tour preceding the White album. This was a brief window before they became superstars.

I missed it by two years.

My first Fleetwood Mac show was on the Rumours Tour in 1977.
I was 7 years old.