Biggest size difference between 2 elite fighters that was overcame ?

Yah, this is understood - please read the first line of my post that you quoted.

 

Elite is a subjective term.

It is also a term that stifles legitimate debate at times.

 

Holy ****. Good spot. That is an insane weight pull however you look at it - a whole Jr. Welterweight’s worth. I wonder how tall Millard was - hopefully at least taller than 5’9”.

 

I was able to find a few newspapers that mentioned the contest but none said Zender's height. I assume he was taller than Fitzsimmons but I have no idea by how much.

 

Primo Carnera 260.5 lbs Vs. Jack Sharkey 201 lbs.
This fight should also be mentioned, because both boxers are definitely "elite"; it was a fight for the HW Championship.

 

Suga Valuev

 

Cheers. I just found this on Instagram (see below), I can’t vouch for its accuracy but it does refer to Millard Zender as a giant and giant Alabaman - so that’s a fair implication of reasonable height also.

So, it sounds like Millard reasonably had the height to match his weight without necessarily being grossly overweight or obese.

Fitz amazing P4P power certainly is well documented and it terms of build from the waist up, he def. looked the part.

https://www.instagram.com/thyssterboxing/p/CODr3T3MH_l/