Technical side-note: Add-a-Leaf we would generally suggest a minimum 200kg of load, otherwise, an over-lift situation may occur.
The basic idea of the add-a-leaf is to add more strength and support to the spring, lift is a bi-product of course, which in many cases can work in our favour for ride quality, but if the weight is not present there is not enough force to properly compress the spring.
Different models of vehicle react differently to the add-a-leaf, a light Hilux, for example, would certainly lift a fair way as you can see.
For light or no load vehicles, I would still be choosing the A springs, or B springs max.
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