I'm 5'9 I think, was 65kg skinny fat, nek minit after 6 months of we'll say 'bulking' eating what ever and training 77kg, got over being chubby, dropped down to 70 flat again but wasn't happy skinny bitch again, then after about a year I'm sitting about 74kg & happy atm.
My point is, not hard to change IMO just watch what you eat - I don't count calories or any of that hippy shit either. No need if you have a pretty consistent diet.
My new goal is 78kg and still being lean-ish by the end of the year, trying to get me some more gainzz.
Still a long way to go, but joined a new gym and training about double as hard as I was before, gonna have to start eating a shit load again.