Nels Cline

https://www.pinterest.com/pin/247909154457475000/ (Bottom left in photo, unnumbered black pedal between #12 and #15)

Nels Cline's use of a Demeter TRM-1 Tremulator was listed, photographed, and detailed quite extensively on a now-defunct website/gear journal Cline maintained himself in the 2000s (last viewed around Fall 2008).

If I recall correctly, Nels Cline explained how it was rarely used on his touring pedalboard by the time of Sky Blue Sky, but was still used in the studio. On tour it had been bumped from primary tremolo duty by a Fulltone Deja Vibe.

Now that Cline's old website is gone, the only reference I can find of him using the Tremulator outside of this random pedalboard picture from 2005, is his remaining inclusion in the wikipedia article for the TRM-1 and a few mentions in old messageboard threads, but no direct sources seem to exist anymore.

https://en.m.wikipedia.org/wiki/Demeter_TRM-1_Tremulator

https://www.thegearpage.net/board/index.php?threads/nels-cline-pedals-examined-in-which-songs-and-how-does-he-use-them.928958/

EDIT: Found direct source in a March 2005 issue of Guitar Player magazine, featuring Nels Cline on the cover. Nels directly states his use of the Demeter Tremulator on page 54 (highlighted in picture), and is pictured with the Tremulator in the bottom left corner of his pedalboard on page 60.