Retirement tax questions

Hi, I have a similar issue sort of the other way.  I need to make the 'ROLLOVER" entry go away and to be able to enter the taxable portion of the rollover to reflect my oopsy (partial conversion of traditional IRA funds to Roth) in 4b.  Is the solution to also edit the 1099-R, and if so, how (like what do I have to pick to make it show up in the 4b field)?  Thanks.