Obviously as heavy as he can while still being smooth and fast. I'd say about 153-155 max. This will give him a big advantage over JMM.
I dont think he will gain more than 6 pounds so if the weigh in limit is 144, 150 at the most. I think 148 is a good guess but.
Fighters tend to wiegh more as they get older...well Floyd is 2years older since he last fought, expect him to weigh a little bit more.
Floyd will weigh in at 147. By fight time , he'll be 155. Marquez will weigh in around 145 and weigh the same around fight time. The naturally bigger Floyd will have 10 pounds on Marquez when they square off.
147. He's never weighed more than 149 for a fight. He doesn't cut more than a few pounds since he moved to WW.