A single AAL will stiffen the pack, several AAL's (I have seen a 1500 with 3 on each side) will make your chiropractor rich. FWIW the difference between my wifes 2500 and my 3500 spring pack is a single leaf in the main spring, and an overload above the pack on the 3500.
I've taken several vehicles to a local spring shop and had a leaf or two added. They do all the dirty work and it costs no more than the purchase price of a load leveler add a leaf.
Life can only be understood backwards; but it must be lived forwards.
- Soren Kierkegaard