Retirement tax questions

Thank you Opus 17.

I know most of what you wrote and understand the "prerequisites" for the traditional IRA->Roth IRA conversion to make it have sense.
- have enough money to cover living expenses until RMD
- have enough money to pay taxes for the  conversion
Also, I need to ensure it doesn't affect my Medicare too much. 
Ideally, I would like to stay in 12% tax bracket.
Knowing my moderate income from my existing investment, I would like to be able to run numbers.
I definitely know if I don't have such a conversion done before SS starts and then RMD, I will be hit by a much bigger tax and Medicare. 

My main question remains: how do I get last year's return in Forms View if I used the Online version of TurboTax and don't have a downloaded version?