Well, Ive got my own lathe....so not much to tell.

Take it off, pull the sensors, plate and shaft.
Protect the bearings from metal chips, mount in a lathe, bore out restriction under the plate just to the bearings to make it 60mm just like above the plate. You can go to 62 if you want, but you would have to make/source your own plate. Believe me Ive been searching for 62mm plates for a while and cant find em.
I also glass beaded the exterior...again using ear plugs or vac. tubing to protect the bearings. Cleaned it well, regrease the bearing, assemble, adjust the plate, and install.

Always Flash the ECU by grounding the pos. cable for 30 seconds, reinstall the cable, turn key to on position, turn headlights on, turn off.
Computer will now relearn the new modification for the next 50 starts.

Believe me, you wont be disapointed!