Rear leaf spring questions on settling

[67CamNKC]

I've noticed that I have a drivers side rear corner sitting an inch lower than the pass side on my 67 camaro. The car has been sitting on these new 1.5" Hotchkis drop springs for a year. It gets taken around the block a couple times a month (still building and not street legal yet). The rear shocks are not on the car. The car is still pretty light with the aluminum LS and T56 conversion, no glass, no interior, etc. Could I have one settling or do I need to look elsewhere? I am running Global West subframe connectors that weld in the rear and bolt to the rear of the subframe. Not sure if I should loosen those bolts and see if it help (bind maybe?). I really want to drop the back of the car another inch, but was waiting to see how far these springs settled.

Thanks,

Shannon