Cut the leg off parallel to the bottom of the cargo pocket.
(save scraps for future patches!)
I planned to leave enough for a 1” clean-finish hem, but had to cut more because the knee rip was still in the way.
Even up the legs by checking the pants laying on the side and view them from the back. If possible, have the pant’s owner try them on to see how your cut looks.
Turn under ¼” plus ½” (or more if you have enough) for a clean-finish hem.