I cut mine off, but really don't know how much. I pretty much just eyballed it. It sits pretty level with a full load on the bike, the front might be 1/2" from the ground when unloaded. Obviously they splay a bit with the load.
I also have had a problem with the bolt loosening, even with lock washers in place. I tried some locktite recently and we'll just have to wait and see. The bike has a kickstand plate for mounting and I still couldn't get it tight enough.
Marc