It's not a B or an H. 1 or 2 or 7 are more likely.

Take it one step at a time. The money Out, is a 1099-R with a code for the distribution. The brokerage nearly never knows what happened to that money. So, the 1099-R out code will simply explain the removal of the funds. You don't make up the code. It will be on the 1099-R from that brokerage for that tax year. It might be Regular distribution, or marked also as Early, no known exception. There might be an indication of taxable, if that brokerage was tracking Basis. In this scenario, Basis is not total contributions. It's total post-tax contributions, when we are reviewing Tradition IRA, 401(k) or anything non-Roth.

Then, the Form 5498 is your due diligence to show the money was in fact redeposited (if indirect) or transferred, for the Roth account. If they did indirect, it has to meet the rollover deadline.

The 1099-R worksheet entries are where the tax preparer uses the code to explain what happened to the money. That's where you put Conversion, and that makes some amount taxable. If there was never any post-tax basis in the Traditional IRA, then the entire conversion is taxable. If there was any post-tax basis, then the conversion is pro rated taxable. There is no picking and choosing for a conversion for only Basis, in other words. Only a Roth IRA has ordering rules. The Trad IRA, SEP IRA and SIMPLE IRA are all aggregated for purposes of the big bucket of funds that will be examined for basis or not, and total combined FMV is used for pro rata.

Hope that helps.