I've got the 90 Deg petcocks waiting in the wings. But respecting the elegant simplicity and correct looks of the original Ewerts I decided to attempt to refurbish the original petcocks. I've received corks and disassembled the plunger.

So.... How does one properly reassemble the petcock with any hope of proper function?

My first issue is the size of the cork. It seems a fair it large for the bore. Is this where the boiling water comes in? Does boiling allow the cork to compress into the bore?
Dry, I don't see it fittin'
https://i.postimg.cc/HnwCV639/IMG-2666.jpg

Thank you