Input the return so that it matches the original, then make a copy for future reference and follow the instructions at https://accountants.intuit.com/support/en-us/help-article/amend-tax-return/amend-individual-return-1...

Agreed, and TIL something new, I wouldn't have thought to keep a separate Lacerte file of the original filing I rebuilt versus the amended Lacerte file. That could come in handy if there are issues down the road (rare but possible)! Thanks for sharing!