Big Kid… I would start by working on his upper half. This can and will get better by just having a catch. He needs to extend this lead side out higher meaning his glove, and keep his arm lower until his foot just about strikes the floor. I have a bunch of still shots of pitchers on my Facebook page, search : everything pitching or pitchingU. All pitchers are different but, there are several positions that are common in a good delivery. The baseball on the backside should be below glove level. This will also help hide the baseball from hitters making him more deceptive. For starters I would work on that.