Contrary to what has been said above, the bearing pre-load isn't set cold. According to the handbook the correct procedure is to run the lathe for 30 to 60 minutes to warm up the spindle. The adjustment nut should then be loosened until play is observed in the spindle ( I use a dial gauge to monitor the end float). The adjustment nut is then carefully tightened until the end float is just zero and then tightened another 1/16 of a turn and locked in place with the grub screw.
The above procedure would seem to prohibit the use of Loctite as it will set before the adjustment can be made.
As long as the finish on the spindle is good it shouldn't be necessary to grind it after plating. You only need about 1 thou of plating so the finish on the spindle will come through on the plating. Someone suggested a home nickel plating kit. It's about 40 years since I did any nickel plating at home but it wasn't too difficult so I think it's worth having a go. You will need to mask the screw thread as you don't want to build that up.
One more observation. From your photos you seem to have flat disks instead of the part 10A-3 dust cover shown in the parts list and fitted to my Atlas. It may be that this was a design change for your split casting version of the headstock but it's worth checking.
Russell.