Congrats dude!
I'm trying to do the same at the moment too and it definitely isn't easy. I got up to about 230 at my worst, and stayed there for a long time. In the last month I've dropped a little over 10 pounds (sitting at 212 at the moment) and hopefully can get down around 200. It's not 120 pounds though, that's is without a doubt something to be proud of!