Yep. Been there, done that. After fighting this issue for years on different cars, I finally bought some Hellwig helper leaf springs. I mounted them on top of the rear segment instead of under as they were supposed to be mounted.

That way they are completely out of sight. And I can adjust them to get the height that I want. If anything ever sags, in just a few minutes, I have the car right back where I want it.

No guess work, saves a lot of time, money, and aggravation. And nobody knows they are there.