At what weight would Mayweather have to beat Pacquiao to become p4p No.1?

ok this is only my opinion and would probably put floyd at #1 if he beats pac at 143 or 144 catchweight. that is primarily because not only with floyd's side but with pac's side of the equation. floyd beats pac,floyd goes up, pac goes down. if floyd fought cotto or mosley at 147, floyd goes up but pac would not go down and would still retain his p4p ranking.

but yes, i do get your point. floyd is the naturally bigger man than pac that if he wants to get the fullest credit, he must beat pac at the weight most comfortable to him.

 

Its weird, all I hear is that Floyd is such a small guy and was great at SFW. For a small guy, making 140 is easy