My new rangefinder had a rattle and the rangefinder window only went part way. So with my statue of Dean in the window and incense burning I cracked it open.

Top removed exposing rangefinder

Back with inner lens plate removed exposing focusing works.

Top view of mechinism showing the brass slider that supposed to hold the lens.

Rangefinder removed, I had to remove the whole deal to get the brass slide out.

Slot for the brass slider.

Top view if the slider mechinism

Brass holder that's supposed to have the lens in it.

Mystery rattle, the lens.

Slider removed.

Slider back in place and yes I had to chase that spring about 8 times.

Back in place showing the adjustment screw. I adjusted it in my house because it was late late at night. I used another rangefinder and checked it at 15, 10, 5, and 3 feet. I hope it's right.