Possibly doing a large Roth Conversion this year

This is my first year of retirement.  I somehow was able to go the entire year so far without withdrawing any funds from my IRA or 401k.   I decided instead to sell the profits from my tech stocks which I bought at a low during Covid.  I had $36,000 dollars of realized gains.   I also withdrew $4000 RMD from my inherited IRA from my father for an Adjusted Income of $40,000 , which I have paid my living expenses so far this year with. .

 

When I did a 1040ES, with my all my deductions for being over 65, with the standardized deduction subtracted from my Adjusted income.  I currently owe no or very little income taxes this year.    I think this would be a perfect year to do a large Roth Conversion of a $100,000 dollars.   Do you agree that this would be an excellent year to do that large a conversion.   I realize that it will still be painful in April to write a large check for taxes that I do not actually owe yet.   Do you agree that I should do this and how much do you think the Roth Conversion could cost me?