In my case, it has been a while and I am guessing that it was about an inch difference. My old stops were right on the axle housings and I did not want anything impacting the brand new 9" setup. Also, when I initially cut the factory mounts out, my rear springs had been re-arched and it was way too tight in there. I have since had that reversed. Finally, the roads here in Colorado Springs are terrible! Ruts, potholes, rain culverts.and this Blazer is LOW. I am regularly close to the stops, but the Belltech SP chocks are very tight. This thing rides like a brick. I may end up having to put an inch back into the front and rear once the drivetrain swap is done.