Non deductible IRA contribution

Taxpayer makes IRA contribution which is non-deductible every year. But he did not file any of the Form 8606s. Now he is looking for remedy.

Let's say there are 10 years of missing Form 8606, does he have to file an amended tax return for each of the 10 years? Note that none of the figures on any of the original tax returns will change since the contributions would still be non-deductible and the only purpose is the report the contributions in order to establish the tax basis.

Would it be an allowable way if he only files an amended tax return for the most recent years and attach the Form 8606s of all the 10 years?

Found this on multiple other sites, but can't seem to find the IRS source right now.

"Although Form 8606 is normally submitted with a timely-filed Form 1040, the IRS will process a late-filed Form 8606—even one that is filed after the normal three-year statute of limitations for claiming a refund has expired. The Form 8606 can be submitted without a Form 1040 or a Form 1040X."

The penalty for filing Form 8606 late is $50 for missing forms up through the 2017 tax year. The IRS sometimes waives this penalty if you can show reasonable cause for the delay.

There are some good articles on the internet .Google the words "Late filed form 8606" . I would place particular importance on the article from Ed Slott who is the guru of IRA's . I would not voluntarily pay the $50 late fee for each non-filed 8606