I am currently taking Test Enanthate and injecting 600mg every 3 days into my glutes. I am 195 lbs 5'10 and work out 6x a week. I have gained 18 lbs so far doing this over the last 5 weeks. I was given some Letrozole to use in pct. I was wondering how much to use and when to start it? Also it is an injectable...so what gauge needle is best and what injection site to use?