 Taking a design lead from the US parent, a well overdue new 10/12/15 cwt range was therefore decided upon, to be of the forward control type all based on the same 'outrigger' chassis.With regard to this 'outrigger chassis', Cab and chassis windscreen variants, (subsequently described as 'open' back) differed from the van, estate car, and express bus body models, (subsequently described as 'closed' back) models by the addition of an extra rear crossmember to support the spare wheel carrier and to close the rear ends of the chassis horns.On the 'closed' back models the nature of the rear bodywork meant the rear crossmember could be omitted for this purpose.