well, i'd tweak that a bit.
instead of shooting every 5 days, just go twice a week, like Mon-Tur or something.
also, you need to wait for the sustanon to clear (like it's been mentioned above) before you start PCT...
also, no need for Nolva at 40 mg/day. 20 mg/day is just fine
here's what i'd do:
Weeks 1-12: sustanon 500 mg/wk
Weeks 1-14: Arimidex @ 0.25mg/EOD (and adjust if necessary)
Weeks 15-20: Nolvadex @ 20mg/ED