Fixing a Loose T-20 Calculator Panel

Problem:

I've got a loose setting slide switch on my T-20 and I want to fix it. Something is rattling around in there. I took the top cover off, but I can't get any further.
Solution:
The metal clip that snaps on the inside is what holds the slider in place. There's also a big ball bearing that provides the clicks. There are 2 screws which hold the top circuit down, the back circuit just sits in 2 slots. There's a switch on the back board which is supposed to engage the slot on the slider.

Be careful as parts of the circuit will remain "hot" with close to 200V even after the flash has been fired full dump.

contributed by John Hermanson