Recording 1099-R for excess distribution

I'm confused on this. I have 1099R for an excess contribution with a distribution code of "8J" I downloaded from Vanguard. I am 66 so this is not an early distribution so this should not have a penalty. After processing it, in the Other Tax Situations I was prompted for how to reduce the taxes owed. One option is Other (including being over age 591/2). I selected that, but don't know what amount it is looking for - the gross distribution or the taxable amount?  It also bothers me that it says on this same screen that it doesn't pertain to IRAs, but this was an excess contribution to a Roth IRA. Help!