Floyd has made it very clear...if you want to fight him you have to meet 3 criteria:

1- be clean - you must have random tests done in advance of the fight
2- be marketable - gotta be able to put asses in the seats and sell the PPV (which rules out most everyone on this site)
3- not be under contract with Bob Arum

If Pac and Bradley really want to fight Mayweather so badly then that's all they gotta do. They've even already passed 1 of the 3 since they're both marketable.
That just leaves 2 simple little things.