Lawrence Dunbar:
Well I prefered the plank alloy type of body which I had on my S 20 Foden tipper, In those days it was good for Tar jobs , Which of course was a better rate than dry stone loads, The good old days Eh,
Tarmac was 80 pence per tonne more than dry at our quarry, some places paid the same rate for both though. You needed a really good insulated body to carry wearing course though, all the bodies were tested with thermal image cameras when loaded and any (mostly the lightweight ones) with major cold spots meant they could only cart base courses. All academic now though as the tarmac plants have long gone, as have most of the other quarries in the area! 
Pete.