[knomadd]

You don't "NEED" drop spindles up front. They are preferred for sure, but you will likely have to do a disc swap at the same time. I don't know of a drop spindle that will allow you to use drum brakes, so your brakes are important in that case.

Drop spindles will give you 2"-2.5" drop, depending on which style and company you buy from (I think CPP's modular spindles are 2", but their standard drop spindles and other companies are 2.5") This will keep your ride quality the same since your will be able to use the same springs and shocks. If you want lower, add drop springs, and possibly drop shocks (usually for 3" or more drop spring).

As for the rear, a drop block will be similar to a drop spindle... allowing you to keep a better ride quality, but I would not recommend more than a 2" block. Go with drop springs for the rest of the drop you want, and add shock relocators to give you a good angle on the shocks.

Drop springs will give you a harsher ride the more drop you want. So a 2" spring and 2" block will give a better ride quality than a 4" spring alone.