Eat like you've never eaten before. You have a good base, but it's mass time bro. 7-8 meals a day. I had a buddy that was about your build (he weighed 140 though) and I've been training him for about 6 months now and hes about 165 now and looking swole. Your gifted with a great metabolism like him, so eat, eat, eat and watch yourself grow. Good Luck Bro.