Hello @rbelden,
You're on the right track in setting up a payroll item and creating a paycheck to pay your 401K loan but I'd recommend contacting your accountant. He/she can help and guide you in properly recording your 401K loan repayment.
For more insights, here's an article you can read to learn more about how to track the repayment of your 401K loan: Deduct 401(k) Loan Repayment from a Paycheck.
Please let me know in the comment section down below if you have any other concerns. I'll be always around ready to help.