As Purdy said, the Phaetons used an eight leaf. You might swap for a Roadster 7 leaf, or just remove a leaf or two from your spring. Are you also going to lower the front?
Seems like it would look strange to lower the rear and leave the front stock. If you have 4 or 5 people, I'm not sure you'd want to remove any springs.
You'll need a spacer plate if you remove leafs, or the U bolts won't clamp the spring tight.
If you do take a leaf out, don't take the top one. It has tapered sides that give clearance in the radius of the chassis. Without this, you run the risk of cracking your chassis in that area.