Roth Conversion Tax Calculator

I need an Excel calculator for evaluating Roth conversion tax liabilities, annuity bonuses, and overall financial impact.

Key Requirements:
- Calculate tax liabilities from Roth conversions
- Calculate annuity bonuses
- Assess overall financial impact

I need assistance in refining my existing formulas. I will provide examples and references for preferred calculation methods.

Ideal Skills:
- Proficiency in Excel
- Strong understanding of tax implications
- Financial modeling skills
- Experience in refining complex calculations