both of my 71 C20 CE21034 Longhorns have leaf spring HO52 axles..
both small block 350, one manual trans, one auto..
both 'Custom Camper C20' badged / Z81 Camper Specials..
ochre is Z84 Custom Sport Truck, red is base model with customer ordered moldings..
both farm finds, unmodified / unmolested original equipment..
see SPIDs for other options, hope that helps