I tried a bit more systematic appraoch, adding up fighters' ranks from my top 50 ATG rating. If a fighter fought before or after his prime I took his score times 2. If a fighter was a shell of his former self (Ali vs Holmes, Tyson vs. Lewis, Louis vs. Marciano, post-comeback Holmes, Foreman) or very green (Langford vs. Johnson 1906) I didn't consider it. Also, a top 20 fighter had to be involved, and both had to be top 50. Possible that I may have overlooked some fights.
Here are the top 50 haevyweight fights AT thus assembled.
To my chagrin, Lewis (7X2) vs. Klitschko (45)==59 just failed to make it.
1. Ali (1X2) Foreman (5) 7
2. Ali (1X2) Frazier I (9) 11
3. Ali (1) Liston (6X2) I and II 13
4. Foreman (5) Frazier (9) I 14
5. Ali (1X2) Frazier II and III (9X2) 20
6. Louis (2) Schmeling I (19) 21
7. Louis (2X2) vs. Walcott (20) I and II 24
8. Ali (1X2) vs. Norton (25) I II III 27
8. Liston (6) vs Patterson (21) I and II 27
10. Louis (2) vs. Baer (26) 28
10. Holmes (3) vs. Norton (25) 28
10. Foreman (5X2) vs. Frazier (9X2) II 28
13. Spinks (24) vs. Holmes (3X2) I and II 30
14. Wills (15) vs Langford (8X2) in 1916 31
14. Marciano (11) vs. Walcott I (20) 31
14. Ali (1X2) vs. Quarry (29) 31
17. Johnson (4) vs. Jeanette (28.) in 1906 32
18. Tunney (10) -Dempsey (12X2) 34
18. Charles (14) vs. Walcott (20) I 34
20. Johnson (4) vs Jeffries (16X2) 36
20. Langford (8.) vs. Jeanette (28.) around 1910/11 36
20. Holmes (3) vs. Witherspoon (33) 36
20. Ali (1X2) vs. Young (34) 36
24. Wills (15X2) vs Langford (8.) in 1914 38
24. Frazier (9) vs. Quarry (29) 38
26. Marciano (11) vs. Charles (14X2) 39
27. Louis (2) Schmeling II (19X2) 40
27. Jackson (22) vs. Corbett (18.) 40
27. Ali (1X2) vs. Lyle (38.) 40
30. Liston (6) vs. Williams (35) 41
30. Lewis (7) vs. Holyfield (17X2) 41
32. Schmeling (19) -Sharkey (23) I 42
32. Marciano (11) vs. Moore (31) 42
34. Holyfield (17) Tyson I and II (13X2) 43
34. Ali (1) vs. Patterson (21X2) 43
34. Ali (1) vs. Terrell (42) 43
34. Louis (2) vs. Conn (41) 43
34. Holmes (3) vs. Weaver (40) 43
39. Bowe (27) Holyfield I and II (17) 44
39. Foreman (5X2) vs. Young (34) 44
41. Langford (8.) vs. McVea (37) in 1911 45
42. Charles (14) vs. Ray (32) 46
43. Dempsey (12X2) vs. Jack Sharkey (23) 47
44. Louis (2) vs. Jack Sharkey (23X2) 48
44. Ali (2X2) vs Shavers (44) 48
46. Louis (2) vs. Carnera (49) 51
47. Jeffries (16) vs. Corbett (18X2) II 52
47. Walcott (20) vs. Ray (32) 52
49. Liston (6) vs. Machen (48.) 54
49. Wills (15X2) vs. Jeanette (28.) 1913 58