Aloha I am wandering what you guys think of this smoker design? 1. Is my smoke box large enough? 16" W,27" T, 14" Deep 2. My smoke stack extension . Should it come down to the first grate or the bottom cooking grate? 3. Had it fired for over 6 hours and could not get above 160. 4. Inside the fire box the grate is only about 2" above the firebox floor. Mahalo in advance.