1 tab is 2.5mg so 1ml.
I doubt your letro is 25mg/ml. you might want to verify that dose. Is it 2.5mg?
I would use 25mg of Aromasin daily to balance out your E2 to Free T for libido. Letro for gyno is 1 tab daily for 10 days and then quarter tab daily after that if you continue the prop.