You're over thinking this, just take them and see what works for you.
That being said, are you taking 3 doses per day, each dose being 45mg of ephedrine and 400mg of caffeine? I used EC a lot in the past and that seems high to me, so much so that your sleep is going to be impacted.
Ease into it, there's no reason to go whole-hog the first day.
I find 25 mg of E and 200 mg of C when I first wake to be a good amount, then again at noon. If I need a bit of a pick me up in the afternoon i may take 8-16 mgs of E with a cup of coffee.
Good luck, don't be stupid, and experiment to see what works best for you.