Kurt Cobain utilized a Fender 6G6A/B Bassman amplifier during the recording of the album "Nevermind." This information is corroborated by Dave Friedman, who personally delivered the amp to the studio, as detailed in the "Live Nirvana | Equipment Guide | Kurt Cobain's Amplifiers and Effects Pedals."

Billie used Mike’s Bassman (behind him) to record Bobby Sox.

https://www.guitarworld.com/features/green-day-billie-joe-armstrong-saviors-interview

You can clearly see Paul using a 1963 blonde Tolex Bassman in this picture.

In this photo you can see George sitting in front of a Blonde Bassman amplifier (according to Andy Babiuk, a circa 1961 to 1963 6G6B model), holding the famous "Rocky" strat. This amplifier originally belonged to Paul but was used increasingly by George in the studio throughout the 60s. When the Beatles broke up George wound up with the amp and to the best of my knowledge it currently belongs to his son, Dahni Harrison. You can see it behind Dahni Harrison in the recent "Concert for George."

In this interview on That Pedal Show, Noel Gallagher reveals at 1:27:50 that he recently purchased a 1963 Fender Bassman head and speaker. It is unclear whether he has used this on any recordings yet.

John can be seen playing through a Blonde Fender Bassman head and matching 2x12 cabinet at various points during the Imagine sessions. The book Imagine John and Yoko misidentifies this amp as being a Showman, but in videos the Bassman name can be seen pretty clearly.

According to an interview with Billie Joe Armstrong in Guitar World by Richard Bienstock, Billie Joe used Mike Dirnt's Fender 'Brownface' Bassman 6G6A/B (1962-1964) to record "Bobby Sox."

In this photo the head of this amp can be seen used in a pair of 4x12 marshall cabinets.

Mike Campbell uses the Fender 'Brownface' Bassman 6G6A/B (1962-1964), as confirmed by its listing on Reverb. The amplifier, identifiable by Serial: BP03588, and its matching 2x12 cabinet are noted for having minor cosmetic blemishes and a slightly scratchy volume knob on the "Normal" side, which reflects typical wear from extensive use.

At 12:55 in this Rig Rundown, Brian Setzer’s guitar tech, Tyler Sweet, discusses the Fender Bassman Amps. “They range from 1961-63 era. They're all brown face, all 6G6B's. Incredible amp. Everybody’s in search of them these days.”

At 8:00 we see Deaner use the amp head slaved with his masa/boogie head and cab

A 6G6 cabinet was used on "Brown Sugar", as stated by mix engineer Jimmy Johnson in this September 21, 2018 ProSoundWeb interview.

And guess what we came up with for Bill Wyman? Do you remember those Plexiglas body basses that were around then?

I checked with David Hood later and he says it was a Dan Armstrong. So to the best of our recollection, that’s what it was. He played through David’s Fender Bassman setup, the tube head and separate box.

(...) Did you have a mic on the bass amp?

Yes, the bass guitar mic was an RCA 44. We didn’t have direct back in those days.

An image of Hood's Bassman rig, taken from this March 1, 2019 al.com interview, reveals a blonde 6G6 cabinet as part of the stack.

That said, the bass amplifier rig Hood used for his classic Muscle Shoals Sound Studios work is a Fender Bassman amp head and blonde Fender speaker cabinet.

In 2016, Muscle Shoals Sound reopened at original Sheffield location 3614 Jackson Hwy. and restored to retro ’60s/'70s prime. Hood’s rig was returned to the same spot it was during many vintage sessions. Against the studio wall, just left of the drum booth.

Hood thinks he acquired the Fender head and cabinet in the mid to late '60s.

"My father was in the tire business and got hooked up with a purchasing-agent-type place who would connect you with people to buy things wholesale," Hood says. "They hooked us up with Manny's Music in New York, on 48th Street. It's no longer there, but it was a famous music store. I would call and order things from them. I could hardly talk to them because they spoke so fast, but I started buying amps and would sell them to somebody and buy another one, things like that."

(...) From Manny’s, Hood purchased the blonde cab, containing two 12-inch speakers, originally to use as an extension cabinet with the bass amp he was using. He ended up selling that amp. Now he had an extra cabinet. He then purchased a black Tolex-covered Bassman piggyback amp. “And I can’t remember why I did it, but I brought the blonde cabinet to 3614 (Jackson Hwy.) and we started recording that and using the black Bassman head with it, to monitor myself. Sometimes they’d mic it and sometimes we’d go direct. But I used it always as a monitor. In a studio full of loud guitars and keyboards and everything, you just can’t hear the bass well, even with the headphones. It’s getting where nowadays they have so many channels on the recording stuff they can use several channels for a bass. A long time ago you were lucky if you’d get one channel.”