you can do that will no problem other than more sag when loaded.

I had 5 leaves with that shoth thick overload leaf, I run 4 leafs per side with axle on top of them for drop.

I also flipped my shackle when I flopped the axle on top.

you could use drop shackles but they tend to wheel hop..mine did.

I even bust the spring down on the truck and use a long center bolt for the spring pack, then cut it off after torqued to specs. just keep tem lined up as you compress them it the center bolt.

about 8$ for 12" leaf spring center bolts at napa

you might get 1/2" drop with that thick lower leaf only.