MY Contacts VS OTHER Contacts Labels and auto-complete
Once I cleared out the old auto-complete email addresses (thanks DLeoLion!) there was still a lot of junk from the Other Contacts folder in Gmail (Web) in the auto-complete list on my phone.
When you create a new contact it is added to My Contacts.
My Contacts phone numberes are synced with the Contacts App on my phone.
Other Contacts phone numbers are NOT synced to phone.
For years I've have been moving old contacts out of My Contacts into Other Contacts to keep phone contacts list tidy.
BUT Gmail scrapes all the email address info from Other Contacts and adds it to the auto-complete list on phone.
I wanted to clear these old email addresses from auto-complete too, here's what I did:
1) Tidied all old contacts out from My Contacts to Other Contacts
2) Some people in My Contacts have several email addresses. I moved the extra email addresses into their description text box. Email addresses in the description box are NOT synced to your phone.
3) Exported Other Contacts to a 2nd Gmail account:
Other Contacts > More > Export > Other Contacts > Google CSV
then imported into a second Gmail account:
My Contacts > More > Import ...
4) Deleted Other Contacts from 1st email account.
5) Un-installed/Re-installed Gmail App
6) Voila all nice and tidy!
If i want an old email address I will log into my 2nd email account on the web.
You could add the 2nd account to your phone contacts temporarily, but you'll probably drag all the old email addresses into the auto-complete list.
Hope that may be of use to someone
If someone knows a simpler way to do this, please post

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