Thanks for the responses concerning carrying a firearm guys, all relevent posts have been helpful.
Maybe I should try a high-quality IWB holster. I have tried mexican carry (no holster) and its fairly uncomfortable, but not too bad, and a kydex IWB that was extremely uncomfortable. I have a pretty good stiff belt too.
My main probelm is that I dont like my shirts REAL loose like 1.5+ sizes too big. A size L shirt fits me perfect except for the length and it hits me exactly at the bottom of my belt, which is too short for concealing a gun. It is hard finding shirts that arent excessively expensive in a LT (large tall).
Back when I was heavier(215lbs.) before I lost weight, I wore an XL(T) shirt. I could conceal a XD-45 Service fairly well under a dark T-shirt mexican carry.