How to use AR_RECEIPT_API_PUB Procedure Apply_In_Detail to apply partial payments at line level

We are going to have multiple line invoice transactions that will have the possibility of being short paid at the line level.  We want to be able to apply these short payments at the line level using the API as we will have input to provide us the payment data.  I have it partially working at the moment but it is always apply the full line amount on the line level (it is applying at the line level).  I want to be able to apply a partial payment against it.

Any suggestions on what I need to do. I am as far as I know populating the