Retirement tax questions

Thank you for your quick response.  Please clarify as I am a novice here.  Since we are both over 59 ½, for IRS purposes I don’t need to keep any records except our tax returns?  And I have filed 8606s so keep the returns from the first year filed forward?  

If we were to get audited are the 1099-Rs, 8606s, and 7+ years of returns enough for the IRS?

Do I need to keep the 5498s or investment statements?   Thanks Again