And I think I (the wife actually) did ok.
I had to replace the yellowed plastic crystal and sadly the only glass one I had that fit was somewhat scratched.
I’m finding it a bit of a challenge to locate information on the movement. It is the first chronograph I have serviced and it all went better than anticipated except for a mainspring that wouldn’t cooperate.
I am unsure whether or not it’s the original case. The serial numbers do not match but it is a Zenith case none the less, I’m not bothered either way.