OCI - Ex-Indian Citizen no longer has Indian Passport

Hello,

I am preparing my OCI application. I am Indian born in the 1940's and I surrendered mine and my wife's Indian passports and certificates of naturalisation to the Home Office before 1986 to obtain our British passports. We only got our British passports back from them. Unfortunately we don't have any copies of our Indian passports or naturalisation certificates now.

The OCI website states that we need to provide a notarised affidavitt of (former) Indian citizenship and a copy of our naturalisation certificate and (not sure about this) some documentary proof of relationships to parents(?).

Has anyone on this forum gone through a similar predicament? Can you provide any advice on the process to follow to obtain the affidavit, the naturalisation certificate and the proof of relationships (if it is necessary)?

Many thanks for any replies you can give.

My wife and I only have education proof documents if that helps, and we don't have our birth certificates....