Cut out HFCS as much as possible, and get yourself a good upper body workout to keep your arms from getting scrawny. Dieting too hard tends to give the concentration camp look, whereas eating what you want in the most natural form possible (hence avoiding HFCS in favor of real cane sugar or honey wherever you can) will be a lot more likely to get the results you want.
You don't have to be pumping major iron daily, just try to give your chest and arms a bit more attention to match the lower body workout you're already getting.