Good instructions.
I recently replaced the kingpins and bushings in my 49 3100. The axle was std size and needed no machine work but the spindles were worn way past being able to use the replacement bushings.
I wasn't ready to upgrade to a disc brake conversion and I couldn't locate good replacement OEM drum brake spindles to fit my 49.

Had to have a machine shop ream out the spindles to round then make up new oversize OD bushings that were press fit into the spindle. The bushings ID still takes std size kingpins.
It wasn't cheap, $120 per spindle for the machine work and bushings but well worth it for the dramatic improvement in road ability.