External Balanced 360 With new parts still Balanced??

You'll replace the steel with bronze and change the small end weight by about 0.5 to 1 gram. Not a worry.

BUT.... no drill press. You need an interference fit of the bushing of around .002" all around the hole and with a very tight tolerance.... no way you can accomplish that in a drill press. Nor will the hole be straight enough, round enough, or square enough to the axis of the rod. And then you have to finish hone the bushing to a tolerance of something like .0002". It's not a home shop operation.

The shops have special honing machines designed just for this type of work.