So you need to take the left side in yes?
I'm wondering if there is a question in her post.
If those are expensive dress pants belonging to a good suit jacket, "_customer" may want to look for a real alterationist.
It would appear from OP's cryptic message that the pants need to be reduced in size on the left side only. Probably simplest done at the side seam, but not an easy task, as that's usually where a pocket is. Taking them apart and reducing width of the left side at CF and CB would be another (but more time consuming) option (zipper, fly, etc.). Best alteration yet would be to recut front and back of the left side, taking equal amounts out of CF, CB, AND both side seams. Worth it if the suit is a British bespoke suit. Otherwise, not so much...
JMHO
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