G'day. I have a 2006 BF XR8 Sedan. I have a set of Lower (25-40MM) Rear springs I want to fit. I also need to replace the upper and lower spring spacer pads. Does anyone know if I need to use thicker pads to compensate for the shorter springs. I have asked 2 Pad suppliers who don't seem to be able to conclusively answer my question. Any help would be appreciated. Thanks.