Assuming that you now have the truck, take a look at the existing springs to see how much sag they currently have. My original front leafs on my 55 were flattened out to almost horizontal. When I put on my monoleafs, I only got about 1 inch lower because the originals were so flat. It worked for my purpose. See what you have to start with, then you can look at your options - drop spindles, drop axle, etc. to get you where you want to be.
