ILR after divorce?

Hi,

I hope someone could help me with my questions as it is not clear for me if I still can get ILR:

I am a South African passport holder and have been married to a Portugese passport holder for 6 years and living in UK for 5 1/2 years. All this time I was living under temporary residency. We are in the process of divorce now and I would like to apply for IRL so I can stay in UK.
My understanding that applying for IRL is my best choice.I have called Home Office to ask if I could apply and they said that I did have retained rights as
we have been married for more than 3 years and we have both been living and working in the U.K for more than a year.
I have started application process (form EEA4) and have got some questions , hopefully someone here would be able to help answer:

How helpful it is to have a 'sponsor' as mentioned on the forms for my residency?
Do I need my soon to be ex-husbands passport/identity card or can I send a certified copy if it is required?
Why would I need to send his history if I am applying on my own?
Would I need to send marriage/divorce certificates?
Would I need my husbands work history, N.I. number etc?
Should I wait for the divorce to be final before applying?

Thank you!