I have a Win M70 SA 243 Ranger Youth Serial # G2073XXX. My action is the type with the extractor built into the bolt face. My barrel necks down just forward of the action.

Will a M70 SA Featherweight (controlled feed type action) stock fit my rifle? Pictures of this stock show that the barrel channel necks down like my barrel.

I'm quite sure that it will fit, barrel channel may need a very slight amount of work near the action.
The other thing you need is a one piece or 2 piece bottom metal, I believe the youth/ranger came with the trigger guard only and a blind magazine, Featherweight had 2 piece bottom metal (operable floorplate), also one piece bottom from Williams will fit with a slight amount of inletting on the Featherweight stock.
Good luck

It has a hinged floor plate....2 piece, so it should work with little rework.

Thanks, I think I'll give it a try.