One and a half grains of Armour contain about 58.5 mcg of T4 and 13.5 mcg of T3. That will be less than your previous dosage of T4 and Cytomel.
What are you latest thyroid test results and reference ranges? Also, if tested for Vitamin D, B12 and ferritin, please post those, along with ranges also.
http://www.nhnatural.com/images/About_armour_thyroid.pdf