My friend was trying to lower BF and gain muscle mass. I'm not sure exactly how much he weighed, he would never tell me and I don't bother asking again, but I do admit, he was a bit chubby, he lowered his BF a lot, and in addidtion to that gained a lot of muscle mass too. Overall he didn't really gain anything, in fact I think he lost "weight". But hes looking good and that took him over 6 months. (and a little confidence boost too. Hes a cocky little sh*t now, but thats ok)
Unless you go "Hulk" on us, it's going to be hard to do that.