No problem at all, happy to help! 

I have a tool for trial-and-error finding DATA7 fields. Create two clients, make the form appear in one, and compare the DATA7 tables... You're looking for C7_39 for Form 8606 (2023).

I must warn you though, DATA7 has NOT been consistent between years for me. Lacerte changes things up from year to year and you can't trust that C7_39 will still be Form 8606 in 2024, and it might not be that in 2022, etc.

Best,

Steffan