The TML JF are still not as slim as im guessing you are looking for. Im 6 3, 200 lbs and it still is big at the waist on me (and i wear a 16). Furthermore, TML collars are smaller than other shirtmakers, for example im a comfortable 16 usually but with TML i cant button a 16.
You might want to try MTM if you want a real slim fit, or take your shirts to a tailor, both good options.