Is there a way now (years later) to receipt an overpayment and eliminate the accounts receivable credit?

I'm happy to help handle your overpayment and credits, @MarniR. I'll also share some information to guide you accordingly. 

As long as the books are still open, you can link the overpayment credit to the invoices. Since these transactions are accounts receivable, they will impact your Balance Sheet and Profit and Loss. No worries, the balances will settle when reconciling.

Here's how:

1. Go to the New icon and select Received Payment. 
2. Choose the customer name in the drop-down. 
3.  Select the appropriate credit and the invoice in the list. 
4. Complete the other details, then click Save and close. 

For more information, see this link: Handle a customer credit or overpayment in QuickBooks Online.

Make sure that the automatically apply credit feature is turned off. This way, you can choose appropriate credits. See the screenshot below for more reference:

I'd recommend reaching an accountant if the book is already closed. They can help you open the open books and handle the old credits. If you don't have one, I can help you find one.

Moreover, check out the following articles below to learn the different ways to record refunds depending on the scenario:

• Record a customer refund in QuickBooks Online.
• Void or refund customer payments in QuickBooks Online

If you need further help to manage your accounts receivable transactions, message me. I'm always here to help. Keep safe.