In a 1967 photo of Eric Clapton performing with Cream, the Marshall JMP 1959 Super Lead 100-Watt amplifier is visible behind him, demonstrating its use during that period.

Used for ZZ Top's First Album, Rio Grande Mud, Tres Hombres, Fandango!, Tejas and Degüello, as recalled by Gibbons in this December 3, 2009 Guitar World article (reprinted from an interview in the November 1996 issue).

“La Grange”

Tres Hombres (1973)

“That is straight guitar into amp: a 1955 Strat with a stop tailpiece through a 1969 Marshall Super Lead 100. That fuzz sound in the lead and in the front and back end of the composition is just pure tube distortion. Pickup-setting differentials account for the different tones. The opening part was played on what we used to call ‘the mystery setting’ in the dark days before the existence of the five-way toggle switch, when finding that perfect ’tweener [in-between setting of a three-way pickup selector] required dedication.

“That Marshall amp, which was a trusted friend through the first six records, was an import brought over by Jeff Beck’s at-the-time tech. I had four of those babies, and they were my main road amps for years. I ran them through cabinets with those [Celestion] Greenback speakers. They still retain a distinctive, rich, enjoyable tone and are well worth owning. I must, however, advise anyone fortunate enough to find one to beware of the variable power plugs. The 220[-volt] setting doesn’t work very well outside of the 220 countries, as I can tell you from experience. We had more than a few paper-clip nights over the years [due to blown fuses].”

“Tush”

Fandango! (1975)

“The first three albums were recorded exclusively at the Robin Hood Studios outside of Dallas, and the special sound that always seemed to be accessible there was due in part to the fact that the equipment was nailed to the floor and nothing ever moved so you could always count on a sound. Quite a good sound, I must say.

“ ‘Tush’ was Pearly Gates, my beloved Les Paul, played through the same Marshall Super Lead, and we sure enough did stop and enjoy the G tuning for the composition’s slide element. This song was largely straight guitar to amp, but I also utilized a real odd, esoteric device called the Cooper Time Cube, which was a simplistic application of the complex world of physics. In a small rack-mounted can sits a small speaker, right up next to maybe 50 feet of one-inch rubber tubing, which is coiled, spring-like. The sound waves actually take longer to travel, having to make these corners, creating a type of delay which is quite unlike the familiar sound of a digital delay. That was a real left-field piece of gear which they had—and still have, I might add—in that studio. Some of the guitar sounds that appear to be doubled on the early albums are actually the byproduct of that oddball Cooper Time Cube.”

This was the main amplifier Randy used. His setup was stereo.

seen behind dave in this image

seen behind adrian in this image

In a MusicRadar article, Deryck Whibley discusses using a 1979 Marshall JMP 1959 Super Lead 100-Watt as his main amplifier for clean sounds during live performances, with the gain set to 3.

In the video you can see Euronymous playing a Marshall JMP stack. Especially at 00:43.

In this video from Fearless Records, we see on one the guitarist of Pierce The Veil, Tony Perry, showing his touring rig. At this point in the video, he shows us the 1971 Marshall Super Lead 100w Tube Guitar Head.

"Trower’s hottest rig blasted his array of Strats through a pair of 100-watt Marshall JMP-100 Mark II heads feeding two 1960-B 4x12 cabs and had an impressive effects chain on the floor: custom preamp and clean booster pedals, a Dan Armstrong Red Ranger treble booster, a Tychobrahe wah-wah, an octave/fuzz Fender Blender, a Uni-Vibe chorus/vibrato, Mutron II phase shifter, and two Electro-Harmonix Electric Mistresses."

At 1:30 in the video about equipment used for the recording of Spiritual Instinct, Neige says he specifically used a Marshall JMP "super lead I think"

In the description of this video, Andy lists the pedals that he uses for this song:

Matchless Clubman

Matchless Chieftain

Marshall JMP

Hohner Pianet T

Strymon Bigsky

Strymon Timeline

Eventide Space

El Capistan

Naunaber Slate Stereo Wet

Electro Harmonix EHX POG2

Earthquaker Devices Afterneath

Echo Park

Telecaster

In the official music video for "You Will Never Be One Of Us" by Nails, Todd Jones is seen using a Marshall JMP 1959 Super Lead 100-Watt amplifier head, as featured on YouTube by Nuclear Blast Records.