"I am not looking for tax advice, but thoughtful ideas".
Your original questions sounded like asking for tax advice. Tax advice is what we do here and you need tax advice.
" In 2008, the marginal tax rate on $16k income for joint returns is 10% or $1,600".
No. The $16,000 is on top of the other $144,000 of the severance and any other income you had. The marginal rate is 25% and maybe some at 28%,.
Q. Would TurboTax be able to handle this situation correctly or would I have to manually insert it?"
A. You have to manually insert the credit. TT does not do the credit calculation or compare it to the alternate deduction.
Q. on what schedule and what line would this credit go on my 2019 return?
A. In 2018, it went on line 74 of schedule 5. The forms will be changing for 2019.
I, too, recommend that you consult with a tax professional and have them prepare your return.
