A trim strip for lining an opening of an interior panel for a vehicle includes a first trim segment having a panel engaging side and an exposed side. A second trim segment extends outwardly from the first trim segment at a first end of the first trim segment. The second trim segment has a panel engaging side and an exposed side. A third trim segment extends outwardly from the first trim segment at a second, opposite end of the first trim segment. The third trim segment has a panel engaging side and an exposed side. A detachable support member is connected to the second trim segment along a first line of weakness and to the third trim segment along a second line of weakness. The detachable support member includes a datum member arranged and configured to be engaged by a panel datum member during installation of the trim strip at the opening to align and maintain spacing between the second and third trim segments. The detachable support member is removable from the first and second trim segments along the first and second lines of weakness.