Depending on where in life one is, Roth Conversion and Capital Gains On ACA Health Insurance and Roth Conversion with Social Security and Medicare IRMAA expand on the example included in that wiki article.
When you think you are close to FIRE, see Some Important Questions to Answer Before Asking - Can I Retire? | Early Retirement to validate.
Meanwhile, consider the advice in Investment Order or Prioritizing investments (it's pretty much the same advice) to see if that makes sense for you.
Don't know how shareholder services came up with what they show. You could ask....
The calculations you show look correct. The stock spinoff should not have increased or decreased the basis you inherited. The IRS would object to a basis increase, and you would object to a basis decrease.
In the explanation for Line 16 it says
Substitute $45.09 for $40 and the number of shares you inherited for 1,000 and the procedure described there should apply to you. Is that how you see it also?
Are Investor FAQs | Constellation Energy Corporation and https://investors.constellationenergy.com/static-files/9a7b24f2-4a36-4f22-9ad9-831673c6c085 helpful?
Even if the $167K and $10K were for the same person, there would be no need to wait until next year for step #2. It is the non-Roth IRA balance on 31-Dec that matters to Form 8606.
The phrase Roth conversion by itself usually refers to converting pre-tax money in a traditional account to a Roth account. The amount converted is then taxable for the tax year that equals the calendar year in which the conversion occurs.
The phrase Backdoor Roth refers to a two-step process...
Probably not. At least, for most people doing taxable Roth conversions while still working is not worthwhile.
The rollover IRA will complicate the backdoor Roth process. See the wiki article linked earlier for details.
No need for any software if those are the assumptions that will be used. The Traditional versus Roth result is based on marginal tax rates, and with those rates using Roth now wins.
1. Why not use the Backdoor Roth process? Getting money into Roth is better than putting money into taxable accounts.
2. How much do each of you have in traditional IRAs now?
3. Yes, regardless of whether she has a job or not, given your income.
4. The Investment Order suggestions are...