think what you will ... the 79 has coil up front, now why would Toyota do that?
So they wouldnt be the last work ute in the world with leaf springs all round

I think the coils up front and the leaves in the back is a good concept for HD vehicle intended to carry heavy loads .
Its interesting that the Patrol cab chassis were offered with either a rear coil ,or rear leaf.
Landrover Defender went to coils all round in their cc