Fantastic Four #149 (Pt 17) Jaws

1962: Fantastic Four #4 Kirby

1974: Fantastic Four #149 Buckler

Note: The great Roger Kastel, who is known for his Star Trek, Doc Savage movie posters, book covers, etc., created the Jaws painting that was used for the novel's cover--first published in early 1974, a few months before FF #149--and the 1975 movie poster. 

Giant-Size Avengers #1 (Pt 62) Johnny Storm and Whizzer

1970: Fantastic Four #99 Kirby

1974: Giant-Size Avengers #1
Buckler

Giant-Size Avengers #1 (Pt 61) Quicksilver's Stern Face

Eh, not a swipe -- sorry folks 😞

But Quicksilver's always been one of my favorite characters so here for your viewing pleasure (and mine!) are a couple of stern, somewhat sour-faced Pietro pics--first pic by Kirby-Reinman and then by Buckler-Adkins. Love the eyebrows/cheekbones/jawline!

1964: X-Men #4 Kirby-Paul Reinman

1974: Giant-Size Avengers 1 Buckler-Dan Adkins

Giant-Size Avengers #1 (Pt 60) Iron Man, Iron Man...

1974: Giant-Size Avengers #1                 1964: Avengers #5          
    Buckler                                                     Kirby            

The Iron Man images in context: 

1974: Giant-Size Avengers #1 Buckler

1964: Avengers #5 Kirby

Giant-Size Avengers #1 (Pt 59) Iron Man and Nuklo

1966: Tales to Astonish #82 Kirby

1974: Giant-Size Avengers #1 Buckler

Giant-Size Avengers #1 (Pt 58) Vison, Nuklo and Ben Grimm

1974: Giant-Size Avengers #1 Buckler

1967: Fantastic Four Annual #5 Kirby

Giant-Size Avengers #1 (Pt 57) Namor 'n' Nuklo

1966: Tales to Astonish #82 Kirby

1974: Giant-Size Avengers #1 Buckler

Giant-Size Avengers #1 (Pt 56) Thor, Vision, Nuklo and Thermal Man

1969: Thor #170 Kirby

1974: Giant-Size Avengers #1 Buckler

Giant-Size Avengers #1 (Pt 55) Captain America Again

1974: Giant-Size Avengers #1                 1968: Captain America #108
   Buckler                                                    Kirby 

Giant-Size Avengers #1 (Pt 54) Scarlet Witch and Sif

1974: Giant-Size Avengers #1  Buckler

1968: Thor #156   Kirby

Giant-Size Avengers #1 (Pt 53) S'More Thor

Journey Into Mystery #125
(1966) Kirby

Giant-Size Avengers #1
(1974) Buckler