What size t-shirt should a 6'3 23 year old guy wear I am tall and skinny 175 lbs Large usually fits my torso but rides up too high. XL are way too baggy?

You should check out companies that carry LT (Large Tall). Some JC Penny stores will, and any local decorator (embroiderer or screen printer) will usually have access to blank apparel in tall sizes. Good Luck!