I found an Irish tweed jacket with high, slanted pockets, double split in back, and nice buttons of a super color for my kilt. I took it to a tailor with a drawing of what I wanted. They simply shortened the coat.

I took it back and marked the coat in chalk with the precise curve I wanted. They made a straight diagonal cut, stating it would look better that way, and ruined the coat entirely; a shame.

I think I'd take documentation, mark in chalk, and also a photo of yourself in kilt and kilt jacket, so they understand what is needed. Sometimes a picture is worth a thousand instructions.