Only your traditional IRA contribution for 2017 gets reported on your 2017 tax return. The Roth conversion performed in 2018 must be reported on your 2018 tax return. These are two separate transactions. Your basis in nondeductible traditional IRA contributions will appear on line 14 of your 2017 Form 8606 will carry forward to line 2 of your 2018 Form 8606.
