I guess that the answer would be, yes, it could be done.

The question would be, how well would it work and how long would it last?
The 600NE would be a hard one, due to the size of the action required, the strength required to handle the very high breech thrust, the weight required to keep recoil anywhere near tollerable, not to mention the handling of the finished rifle if you managed to sort out the strength and weight issues.

The 600NE will really put the best of any shotgun action to the test in terms of strength.

Personally, I'd love to own a 600NE, but I think it would be difficult to ever achieve adequate action strength, tollerable recoil, and good handling from a shotgun to rifle conversion, with full power 600NE loads.