Check your Form 8606 to review the calculation of the taxable amount of the Roth conversion. As I understand it your Form 8606 should show only $6,000 on line 3 and should show $6,265 on line 8 or (or should show these amounts on the associated worksheet if your Form 8606 shows asterisks next to lines 13 and 15). Form 8606 line 16 should show $6,265, line 17 should show $6,000, and line 18 should show $265.
