Altering Flare Leg Jeans to Boot Cut.
Just cut down to side until past the flare and then sew back together (but cut part of the flaring part off so it is a boot cut).
Answer.
The extra...
You can not, unless you want to cut slits in the side of the jeans, it looks okay but I would just buy a new pair of Flare. Try this website www.BuyandSellJeans.com
Rip out the inside and outside seams until you get above the knee area. For straight-leg pants, mark new seams to be the same width as the leg near the knee area. For a tighter cuff, mark the cuffs...