After you e-File,
get Form 1040-X from IRS website and mail it in with correct Schedule D and changed Form(s) 8949 attached.
Note: When you are not changing any dollar amounts on your Form 1040-X, you can leave all the lines 1-23 EMPTY.
Do not include your old 1040 nor your revised 1040 because they are identical.
Part II explanation: correcting carryforward numbers, tax unchanged.
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