I actually didn't take off the knuckle arms when I did mine, but I had to get a seal puller to get that stupid freaking seal out of there.  but next time I do mine-to install widening kit! I'll be doing that, hey quick question then: How do we know how many shims to put under the knuckle arms? My good buddy told me that the wrong amount will cause the axle to spin irregularly, thus destroying that stupid freaking seal.  TIA!