Because you are using HCG at the end towards the PCT, I see no reason at all why your PCT should take more than 4 weeks.
I've read some stories about users tappering the Nolvadex like 40/40/20/10/5.
This board claims a 40/40/40/40 Nolva PCT, but many studies claim that there is not much difference in increase of Test between 20 or 40mg Nolva daily.
My PCT is mostly 40/20/20/20 but that's my opinion. I've never done very harsh cycles. Mostly Test only or Test + dbol when bulking.