installing warn premium hubs

I just took out my factory automatic hubs to be replaced by some warn premiums, but when i tried to install the new hubs the assembly wont recess all the way to fit in the snap-ring. It seems like the splined piece that resides outside the axle nut is keeping the hub from going all the way in. My question is should i remove the splined piece so the hub will go all the way in and the snap-ring will fit into place? Or is there something i am doing wrong? Thanks for the help