spring perch

I am installing my rear Dana 489 from ECGS, and the spring perch diameter is way less than stock. My stock 35 had a perfect size perch for the spring to seat on and "lock" into. Anyone ever come across this? Am I supposed to just use the retainer and let the spring move around that much on...

While upgrading my rear springs to some MOOG 3227s I confirmed that my rear upper spring perches were rusted....badly. I'm in the process of ordering/welding on new ones and "while I'm in there" I thought about relocating them. Currently my TJ is at stock height. I want to do a lift later, but...