Losing weight to serve!!!

I have always been a big guy. I played sports in high school and lifted weights but all that changed when I entered the real world. SO here I am @ 29 years old and I have decided to make a change in my life. I decided I want to serve my country and join the Army. I walk into the recruiters office and guess what the first thing said was????? You have alot of work to do. Come back when you lose about 50 pounds. Wow.....knew I was out of shape and a little on the big side( maybe more then a little) but I thought they would at least talk to me. Nope, this fat boy has to run. I took the first step back in late november when I cut out all sodas and drank only water. Then I decided to start working on changing the way I eat. Within a month I dropped 15 pounds so now I have to lose another 35. So I started out today with couch to 5k on my ipod. Felt good and did some resistance training after. I am trying to stay away from the scale for at least a week or two. Wouldn't want to get discouraged and lose any motivation. Any tips, tricks, or magic anyone has had success with is always greatly appreciated. Untill the next workout.......run fat boy....run!!!!