you are correct in pointing out the two on the right as being more 'forward control' for the lack of a better word as the coach work has been built 'OVER' the cowl and has the windscreen built at the rear edge of the bonnet (hood) where as the left pair have the cowl, with vent, in front of the windscreen.
I think that all would have been export flat cowl units and the bodybuilder who built the bodies on the Right hand pair has removed the cowl unit when constructing the bodies because of a possible shorter wheelbase with a fairly standard type body being built on them. This was probably an easier way of constructing them then trying to lengthen the chassis.
Cheers
Cliff
