I bet if you put zero on lines 18, 20, and 22, the maximum deferral will calculate as zero 🙂
see if that works........
ps I read the instructions and it does state it is optional, but doesn't state how to decline the option!!
https://www.irs.gov/pub/irs-dft/i1040sse--dft.pdf
page SE-6 on the right.
