I wonder if anyone's had the pleasure of dealing with this case before, and can guide me a little here? This is a colleague's 1970's Omega Seamaster, case 166.066.

The original crystal gasket had turned to an unstable goo and eaten up the chapter ring below it. I've sourced a new gasket 088NS5133 and crystal 063TN5166, which has a very deep groove to accommodate.

There's no chamfer for the case to accept the gasket, it's not immediately clear how this is supposed to compress in a way that...

Oddball 70's Seamaster soft crystal gasket fitment help