The hard part is conforming it - so you did well there. If you have a cr2 file for the clothing, and the cr2 file refers to a wavefront.obj file in the Geometries folder, then UVMapper should work, starting with the default planar z-axis settings IIRC. You have to tweak it by separating and moving the groups around, and possibly remapping and enlarging some of them, but Steve Cox has made that fairly painless, especially in the Windows version. Then you create the new texture template, if necessary pasting pieces of the old texture(s) onto it to fit.