River Kayak for Big Boy

Seriously considering purchasing my first kayak but don't know where to start. My primary use for the kayak would be to shuttle me from one fishing hole to the next on the river, and maybe some fishing from the boat as I drift with the current. My challenge is my size...I am 6'7" and weigh 300 pounds plus. Stability is way more important to me than speed, especially since this is a river boat.

Is there a boat made for oversized dudes like me? What models do you recommend?

Am I crazy for thinking of taking it out on the river (i.e. American and Feather Rivers)?

Last question...can it be anchored in calmer water and fished from?

Thanks for any help.

I dont know jack about rivers but I know big and tall guys like the malibu x factor in the ocean.

plenty of room, comfortable seat you sit on instead of in, extremely stable (stable enough to stand in), very high weight capacity  (600 pounds), since this is a pedal yak your hands are free to fish. 
http://www.hobiecat.com/kayaks/mirage/pro-angler/

Demo this and see if it fits you well...

http://www.oceankayak.com/kayaks/angler_editions/prowler_big_game.html

the prowler big game is one great yak with great stability , high capacity, and plenty of storage . I find a good all around yak for me at 6' and 300#. demo and see for yourself.

Cobra Fisn n Dive has a 600# capacity and is only 12' 6''

http://www.cobrakayaks.com/kayaks/cobracat4.html