Post-war, aluminium was also plentiful, with an excess of it from scrap military aircraft (and a steel shortage) the primary reason that the Land Rover was developed with an aluminium body. Being light, available and easy to manipulate with hand tools, aluminium was the perfect material to introduce to a shed and plonk on top of, say, an Austin 7 chassis. And yes, the Austin 7: let's not understate its importance either. It popularised motoring in the '20s and '30s and was winning races even then.