Hi, I think I finally figured out how to do it. You were right. I would just add the relevant notes from pub 590-a and 590-b and Tax Guide 2018 to illustrate the point.
from pub 590-a
1. Rollover From Employer's Plan Into an trad. IRA
"Reporting rollovers from employer plans.
Enter the total distribution (before income tax or other deductions were withheld) on Form 1040, line 4a." ....Enter the remaining amount, even if zero, on Form 1040, line 4b. Also, enter "Rollover" next to Form 1040, line 4b.
2. from pub 590-b
Are Distributions Taxable?
"Reporting taxable distributions on your return.
Report fully taxable distributions, including early distributions, on Form 1040, line 4b (no entry is required on line 4a),".
So, if one rolled over two 401(k)s to trad. IRA and then converted one of them into Roth, rollovers goes on 4a and conversion (taxable distribution?) goes on 4b and no entry on 4a. makes sense? though 'no entry' note still contradicts 1040 4a/4b Exception 2 rules.
