Okay, bedding job complete on the Model 70 Extreme Weather. I used Devcon Plastic Steel -- my compound of choice. I've bedded a lot of rifles, but never a Winchester.
The lug was straight forward, but the compound is very, very thin on top of the receiver flat; I'm suspicious that it may flake off over time. The good news is that it's so thin, I'm not sure it'll matter. There was obviously a very, very close fit between the two surfaces. We'll see. I'm not apt to redo it at this point unless some of you Winchester guys advise otherwise.
I found the tang area to be tricky. Once you grind away the factory goo, there is very little aluminum bedding block to serve as a "shelf" for the new compound to sit on. I found it easier to block the pillar hole, dam it up with clay in front by the trigger assembly, and make a solid block of bedding. Then, when it cured, I just drilled through the pillar for the action screw hole. I wound up with a lot more surface area for the screw block, and three clean "walls" to keep it from moving. I had to go back with the Dremel and make some clearance for the bolt release spring, etc., which is why it looks a little chewed up.
Thoughts? If you Winchester guys see a problem, please let me know. I'd rather fix it than waste weeks at the range. Not sure about that receiver flat...the bedding there is thinner than a sheet of paper. I am confident that the rig is stress free; it passes all contortions of the action-screw test tightening/loosening test. Both screws bottom out and "hit the wall" almost immediately.