I would run Arimidex or Aromasin during cycle, (1-12 if Adex, 1-16 if Aromasin), and save the Nolvadex for post cycle therapy (pct). Also, 300mg of Clomid is going to make you feel like absolute shit (just what I've read) so perhaps a post cycle therapy (pct) of 40/40/20/20 Nolva might be best...