The needle bar needs to be centered, and the armature bar leveled properly and touching the front coil.

The instructions have you install the needle and tube into the machine.
The needle bar ended up being slightly out of place. But with the main spring mounting screw a little loose, we're able to wiggle the armature bar enough to center the needle bar in the tube.

Quick note: I'll need more time with the tube vise. I'm not used to the flexibility/bend involved with it being two pieces. That and having an Allen wrench ("hex key" doesn't sound as cool) always handy will be new.

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Pushing the armature bar down to make contact with the front coil lets us check coil height, bar level, and the clearance between armature bar and back coil core.

Drew felt the back coil should be a bit higher, so I unscrewed it from the frame, moved it slightly aside and added a shim (0.02”) to boost it up. Then I did a little dance and I made a little love.

This is just a matter of getting the right order. Post, positive solder (red) of capicator, insulator washer, etc.

The diagram makes it easy.