I am filing form 1040x myself (meaning I am not a paid preparer) Must I file form 8867 (Paid Preparer's Earned Income Credit Checklist)?

No i do not think so. UNLESS you are paid to prepare an EITC claim, you do not need to submit the Form 8867 to IRS; Only paid preparers have to complete form 8867; it’s the checklist that a paid preparer uses to figure out if you’re entitled to the EITC. Since you are not a tax return preparer, you need to give the signing tax return preparer the completed form in electronic or non-electronic format.