Alaskan Kings on the fly: Where

Long time no post, but I am back again for some help. Ready for a return to Alaska, will be targeting Kings on the flyrod. I know alot of you guys visit Ak regularly and some have lived there. So I ask your help. I have a list  narrowed to the following. In Bristol Bay area, the Togiak R. is my front runner, then Alagnak R. then there is the Kanektok R. which seems "a bridge too far". I am also considering the Yentna system including, the Talachulitna Cr,,,,. Lake Cr,,,, and the upper Yentna R.
 
The Togiak is my frontrunner becouse though it seems a liitle larger than some it's seems very manageable/readable/fly fishable. It has  strong run of Kings with a strong run of Chums peaking just after the Kings, thus giving an alternative. Oh, and of course there a several hundred thousand Sockeyes. There is a semi permenant tent camp on the river that seems to attract a good number of guys flyfishing for Kings whereas at other lodges they do not promote ff for Kings and cater to the gear fishing guys.
 
Any help will be appreciated, thanks.

I floated the Talachulitna about 5 yrs ago last week of June. There were loads of Kings in the lower section (after it becomes a river). We picked up a few on flies, but would have caught more had we known what we were doing. Mainly focused on trout and just enjoying the trip. There are some good websites out there for info, and the float was actually pretty easy and inexpensive to arrange, assuming that you have most of the camping/ fishing equipment already.

The Nushagak River gets the largest run of kings, its west of cooks inlet. Alaska outdoor forums is a great place to read about all of these streams and rivers