The 3 door cossie roll bar is the same SHAPE, but is thicker.
Th attachment points as far as I can remember are on the outer edge of each arm and the brackets are locate on the chassis section near the top of the springs.
I think there is 10mm/12mm/14mm bars used on the rear of the 3 door shells.
3 door roll bar on 4wd beam ?, the bars are different shape but do not go on the beam.
tabetha