Still if you have to maintain the hub, FW may stay as long as you only repack with grease (and change the cones/axle). It only comes necessary when you remove the races of the hub (if possible, and if finding a perfect match for the hub). That's why an axle comes with a large spacer and the locknut is on the far end: to can drive out the cone with a screwdriver on the side; or better yet, loosen the NDS locknut and remove the NDS cone and drive the axle out of the DS leaving the DS cone-spacer-locknut untouched.