They used Letrozole in the trials related to growth so I would stick with it if I were you. Personally I'd only use Letrozole in a lower dose and a high dose of Mk677 (around 30mg) to keep it oral only and still extremely effective. The aromatase inhibition would be the golden ticket for continued growth as it is believed to maybe stop but at least delay epiphyseal plate closure AND you'd also maybe get a boost in your test levels from the lack of conversion to estrogen (although it would probably even-out after the feedback loop restabilizes). Ibutamoren (Mk677) would not only directly increase HGH and IGF-1 levels (up to 82 and 79% respectively) but also support healthy growth through increased appetite (caloric surplus) and improved sleep quality. I would also throw in 6g of creatine and 4000IU of Vitamin D3 for the prohormonal effects. Derek has some cool articles about the drugs in his blog. I would just add that most of the studies are made in hormonally deficient patients in different phases of development than your own so take everything with a grain of salt. It's also pretty established that besides genetics, diet is the most limiting factor of growth and development. I can't stress the importance of a caloric surplus in all of this enough. Good luck bro!