Led Zeppelin — Metronome Modulations

Metronome Modulation (AKA Tempo Modulation) = change in Metronome Mark determined by shared group of notes on both sides of a new Tempo or Time Signature.
Halves, Double, Quadruples are easiest and most popular:
“How Many More Times”
“The Lemon Song”
“The Song Remains the Same”
“In My Time of Dying”
“In the Evening”
“Fool in the Rain”

Below are given slightly more complex tempo/rhythm manipulations:
(Please note that these are not exact modulations, like one would expect for an Elliott Carter String Quartet.  the examples given below reflect how these tunes were most likely worked out in rehearsal.  Both live and recorded versions, being more familiar to the band, witness slightly aberrant results)