The four "wooden" pieces are actually fiberboard sliders that fit inside the pushbutton mechanism. Unfortunately I don't know of any documentation that covers this. I think your only option is to find another good used pushbutton unit to replace it unless you like Rupiks Cube type puzzles...

Hey bonedoctor I like your new avatar vs the old punchout scene....

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Bill Reimels
Now down to one:
1972 300SE 3.5 W109 (Euro delivery)