I wonder how the "without revealing its precise source" part works. Probably it's this form, https://www.irs.gov/pub/irs-pdf/f1040s1.pdf https://www.irs.gov/pu

I wonder how the "without revealing its precise source" part works. Probably it's this form, https://www.irs.gov/pub/irs-pdf/f1040s1.pdf https://www.irs.gov/pub/irs-pdf/f1040s1.pdf do you just add it in line 8 with type = "stuff"? What happens if they need to audit you if it's the correct amount, won't you have to reveal the source then?