I've got 2846's in my 1665, 1680, and also had one in the Tudor Sub I just parted with. They carry the same exact dimensions as an ETA 2836, so they are a direct replacement:
Only thing is that the ETA datewheels rotate clockwise, so you're stuck with a typical rep overlay for the datewheel.
I haven't had a chance to fit the AS movements yet; both of mine need to be serviced, and I just have not gotten around to doing this. Since Ziggy is out for the Summer, I have some time on my hands...
The Schilds seem to have the same dimensions and stem position as the 2836/46, so I don't suspect there will be any real issues there either. The problem I've observed with the Schilds is obtaining the proper spacing between the dial and movement to allow the datewheel to freely rotate. I have some ideas, but nothing really nailed down as of yet.