1099-R box 7 shows 8 & J. However, the excessive $ amount is added to total Roth IRA conversion, which increases AGI. How can I get it corrected AGI?

Delete the 1099-R. You have to enter the traditional IRA contribution first, then enter the 1099-R so it can match up the already taxed money.

You do not want to file an amended return when this can be fixed now.