CONVERT=YES in the ACIF index parameters, plus specifying the AFP resources to use with the FORMDEF/OVERLAY/PAGEDEF parameters.
You wouldn't normally be given this task without a lot more information -- i.e., the rationale why the data should be converted to AFP, plus the actual resources, and an idea of what the image should look like.
Also, there's a possibility that dramatically modifying the data on the way into CMOD might run afoul of an organization's legal/regulatory obligation to be able to reproduce the data in the same way it was originally presented. I'm not a lawyer, but if you're in front of a judge and you present a different version of the same document that's presented by another party, it would imagine it wouldn't go over very well.
-JD.