We machine the crimp down until the nut and shield are flush. This gives the best contact surface for the upper seal which sits above the bearing. (not shown in photo)
you must lube the seal before installation to do it properly. either by hand or a pressure lube tool which does a good job .
Heating the bearing.
Drivers. Lower race mounted on driver . frame steer tube is heated to aid installation.
driving bearing on lower triple clamp. NOTE:you also need to add the correct shim so the triple clamp does not bottom on the frames steering tube.
The spanner nuts crimp needs to be machined to allow the bearing and seal to seat properly(this is a honda cb750).