It actually fits fine, I mean its a winter top you have to have room to layer. I am getting really good at getting rid of turtlenecks! First again cut down the side . Then cut some of the excess of but leave room to fold down 2X. Also what helps is cutting little nips around the circle in order to ease the folding.
See the nips? Everything is folded 2X and pinned. I then hand sewed everything down while stretching the sweater at the same time (and hence why there are no pictures of this!).
Done! Turtleneck gone! Yay!
Here's to warm winter clothes!!