Need information on dropping a dodge

I'm new here and new to the dually world just converted my dodge 2500 saterday I'm still running the stock 2500 suspension with the 3 inch leveling kit in Front

I heard u can run 1500 springs in the front and it will drop it 3 inches

In the rear I was thing I could flip the spacers from under the leafs to the top so I can use stock u bolts and all then run drop shackels my ? Is does anyone have a pic of a drop that would sit close to this

Here's my truck

How much drop do you want?

I like to have front about 1 inch fender gap an rear maybe 2 inch

What is the gap stock?