OK. If you are trying to piece it together you will need the longer shackles with to go with the flip kit, like these: {Not the short shackles!}
But you will also need the perches for the leafs to be on once you do the flip kit like this:
And here you can see the shackles I have are longer compared to the OEM ones which is what you'll need to get, don't get the short drop shackles
Here's where you can get them:
Lowering Parts - Lowering Shackle Kits By DJM
On Dodges, once you flip the leaf spring under the axle, you need a longer shackle, if you keep the OEM short ones, you will get a 8" drop or so.